1155: Rafa's injury means I'm leaving you a bit earlier than expected but I hope you enjoyed that clash while it lasted. Only another 12 hours or so to wait for your next tennis fix - the indefatigable Piers will be back with you close to midnight to take you through Federer-Davydenko, the Williams sisters and Djokovic v Tsonga - which is the red button match from 0830 GMT on Wednesday, followed by Laura Robson in the quarter-final of the women's doubles. Enjoy.

Pat Cash on 5 Live sports extra: "Andy is in the semi-finals and has got to play a guy who has played three five-set matches so he is a red-hot favourite to beat Cilic. He is in great form, he is full of confidence and is fresh. "I really do think he has a chance of the title. I thought he would be looking at Wimbledon for everything to click and that may still be the case but with everything clicking he is going to try to take advantage of the opportunity he has and the main thing is he is fresh."

872156th on Twitter: "Excellent. (Murray) Only played three sets again. This is just what he needs to give himself a chance."

1147: Andy Murray on his prospects in his Australian Open semi-final with Marin Cilic: "If I play like I did tonight I have got a good chance (against Cilic). The nerves are going to be there because it is the chance to make the final of a Grand Slam but I lost to him at the US Open so I will be looking for revenge. Cilic is obviously a big guy so I am going to keep the ball low."

1144: Injury for Rafa or not - and let's hope it isn't serious - we shouldn't forget how well Murray played in the first two sets there. He will face Marin Cilic, the 14th seed from Croatia, at 0830 GMT on Thursday... and you will be able to follow that on BBC Two, BBC HD, this website and BBC Radio 5 live.

From Kalika in Rickmansworth, via text: "No-one had a two-and-a-half set win for Murray did they? However, Murray played superbly! Hopefully this will be his first Grand Slam!"

1138: It's not the way any of us would have wanted, but Andy Murray sets up a semi-final with Marin Cilic after Rafael Nadal retires with a knee injury with the Scot 6-3 7-6 (7-2) 3-0 up. A shame, it had been a terrific match.

1137: Andy Murray after Rafael Nadal's retirement sends him through to his first Australian Open semi-final: "I've known Rafa since I was 13 or 14 and he is somebody I have always looked up to. He is my favourite player to watch because of his energy and I am gutted for him. I came through a few difficult moments at the start of the match but I played well and I got my tactics right."

Murray 6-3 7-6 (7-2) 3-0* Nadal *denotes next to serve
You sense that Murray is on the brink of victory here, even against a streetfighter like Rafa, who never gives up. That knee injury seems to be hampering Nadal but he hauls his way back to 30-all before a rare loose forehand by Murray gives the Spaniard a break-back point. Murray serves big and deep to save it but is back to square one after breaking his string on the next point. Ace number 12 comes along at exactly the right time... as does 13 - and he holds with a forehand down the line, which Nadal cannot reach.

From xenosys2005 on 606: "Murray's beaten Nadal in a Grand Slam before, so in that regard, he has nothing to prove. Whether Nadal is fit or not, he's been out-classed for periods in this match."

Murray 6-3 7-6 (7-2) *2-0 Nadal *denotes next to serve
Things get worse for Rafa, very quickly. Resuming at 15-15, a Hawkeye challenge goes against the Spaniard and some wild groundstrokes put him in deeper trouble. A forehand flies out at 15-40 and Murray has a first break of the third set... it's not looking very promising for the defending champ.

1125: Good news. Here comes Nadal. He's going to carry on.

1123: On paper, this looks good for Murray - Nadal will need five sets if he is going to rescue this and a knee problem won't help him in that. But, personally, I don't want this match to end - especially not prematurely - or be affected by an injury. Fingers crossed Rafa is OK.

Pat Cash (speaking after the second set) on 5 Live sports extra "When you look at it, this is a perfect opportunity for Murray to get one up on Nadal, who has not had a great few months."

Terkaldinho on Twitter: "Can't hide from it any longer, surely Murray's going to win now, I think I'll cry if he doesn't. Stunning quality match."

1119: Nadal has got injury problems, and is having a medical time-out. It's his knee I think. The right one. I'll keep you posted.

Murray 6-3 7-6 (7-2) 1-0* Nadal *denotes next to serve
Now then. Rafa's got a lot to do here but you still wouldn't bet against him, would you? Well, I wouldn't. The Spaniard shows he is still dangerous with a corking passing shot go 15-30 up but Murray regains control with some authoritative serving and he gets the third set under way with a hold.

SECOND SET
Murray 6-3 7-6 (7-2) *0-0 Nadal *denotes next to serve
Another big serve brings up FIVE set-points for Murray and, when a limp backhand from Rafa droops into the net, that's the second set in the bag. We've been playing for two hours and eight minutes and the British number one is well on top... at the moment, I should add.

stripamnesty on Twitter: "This tie-break could be crucial. Will Murray win and go on to win the match? Will Nadal win and break Murray's spirit?"

Murray 6-3 6-6 (5-1) Nadal *denotes next to serve
Murray starts the tie-break with a mini-break, winning a rally that lasts 19 ferocious strokes... that's been the norm today - it's been a match of ridiculously high quality. Things get even better for the Scot when he takes the next two points on serve thanks to errors from Rafa and he is quickly in to follow up a sizzling backhand down the line and put away an overhead to move 4-1 up. A serve-volley winner later, and Murray is two points away from a two-set lead. Steady now, let's not get carried away...

Murray 6-3 6-6 Nadal *denotes next to serve
The Murray serve (first and second) has been ultra-reliable so far... just the one double-fault and plenty of pace on his second delivery. It doesn't let him down here, either, with an ace - his ninth of the match digging him out of another spot of bother at 30-all. Nadal takes us to deuce after another fierce baseline rally but, after ace number 10, Murray holds out. Tie-break time folks...

From Moon on 606: "Going to be a long game... will Murray have the stamina, and more importantly the desire..? We have seen him fail before when he has done so well. The difference between being a number four (Henman) and number one... and a Grand Slam winner."

Murray *6-3 5-6 Nadal *denotes next to serve
Wow. It all happens in this one, trust me. Murray piles the pressure on, turning defensive to force the errors from Nadal and earning two break-points when the Spaniard fires long with a sloppy backhand. This is a BIG BIG chance but Murray cannot capitalise, with Rafa smashing the next point away before leaving a Murray passing shot and turning to hear it called out. Just. The drama isn't over yet, mind - Nadal slips on the next point to hand Murray another break-point and he has to find an extraordinary volley at full-stretch to save himself for a third time... producing a scream of relief afterwards. So, Rafa in the clear? No. A sloppy backhand puts him in trouble again and he needs his first ace of the match to save a fourth break-point before, eventually, holding. That's why he's the defending champion, I guess: Guts.

Murray 6-3 5-5* Nadal *denotes next to serve
Nadal is one game away from the second set and he knows it, launching attack after attack and targeting the Murray forehand. It's a tactic that gets him to 30-all but Murray is hitting some meaty shots too and puts away a forehand on the next point before a textbook serve-volley winner wraps up the hold.

From cilurnum on 606: "He's very poor Nadal and is there for the taking. He can't serve, can't volley and isn't dominating at all from the back of the court. The powerful looping, top-spin groundstrokes have all gone. I think it would be better for him if he didn't get through and potentially face Federer."

Hmmm. Not sure I agree with cilurnum here. We shall see...

Murray *6-3 4-5 Nadal *denotes next to serve
Rafa needs a good service game too, and he appears to be right back on course at 40-0 until Murray opens up with a couple of scorching winners, the first with his backhand, the second a forehand right in the corner. It's not enough - a big Rafa serve sees him hold - but the standard Murray's returning is definitely giving him lots to think about.

Murray 6-3 4-4* Nadal *denotes next to serve
Exactly the sort of game Murray needed after that little lot. No fireworks here - just an easy hold to love with some thumping first serves doing all the damage. We are all-square again, not just back on serve (which is what I meant to just say below).

Murray *6-3 3-4 Nadal *denotes next to serve
Surely fireworks won't scupper Murray's bid for glory? No chance. His tactic of stepping in to attack the Nadal serve brings him joy this time, taking him to 15-40, and, after a succession of looping forehands on to Nadal's same flank, the Spaniard cracks and sends the ball into the tramlines. That's the instant break-back and we are back on serve again in this second set. That's more like it.

Murray 6-3 2-4* Nadal *denotes next to serve
So, after that little interruption (of about 10 minutes), how will Murray's serve stand up? Er, not great, as it happens. A couple of loose shots and a backhand into the net sees Rafa go 0-40 up. Murray saves the first break-point but an easy volley flies (rockets?) out in the next rally and the Spaniard has the first break of the second set.

1028: Ah, here they come now. Murray has had a change of shirts during that little time-out... he's now in all-white. Here we go again.

1027: Those darned fireworks still haven't finished yet. I'm not sure who is left on Rod Laver Arena at the moment. Players, umpire and line-judges have all disappeared for toilet breaks... and I reckon Ricky Hatton has nipped out to get another pie.

From frenchyinexile on 606: "This looks set to be very good game. Murray looks good but I would never count Rafa out!"

Tim Henman on BBC Two: "These fireworks really do interrupt the rhythm of the match. When Murray comes out to serve next he needs to put in a strong game and not allow the break to affect the quality of play he has shown so far."

Murray *6-3 2-3 Nadal *denotes next to serve
Rafa has stepped up his serve in the second set and turns on the power again to seal another comfortable hold. Ah. Here come those fireworks... lots of them too. We're still on serve on Rod Laver Arena but we're going to have a little break from the action while Melbourne celebrates Australia Day. Very noisily.

From Alex in Cornwall, via text: "Murray needs to keep his level of play up in this set, if he does then Nadal doesn't have a chance. Can't see either player beating Marin Cilic in the semi-final though."

Murray 6-3 2-2* Nadal *denotes next to serve
Not too many routine holds for either player so far, but we've just had two in a row. Murray holds to love. All-square in this second set.

Hatton is not normally a tennis fan

Murray *6-3 1-2 Nadal *denotes next to serve
Ricky Hatton is in Andy Murray's box today - not usually a big tennis fan, our Ricky, this is the first match he has ever attended - not a bad one to choose all things considered. I wonder how many boxing matches Murray has been to, though? Back to what's happening on court, and a solid game by Nadal, who holds to love. Cue fireworks, I think... or maybe not. I didn't hear them, anyway.

Murray 6-3 1-1* Nadal *denotes next to serve
A spot of bother for Murray at 15-30 - his serve had slowed down and Nadal was quick to take advantage. It's only a temporary blip, however, and after recovering to deuce, Murray holds again - he's only been broken once so far but is having to work hard to hold off the defending champ. Those Australia Day fireworks I mentioned earlier are due after the next game. Not the best timing, really.

From Adam in York, missing lectures to watch the tennis, via text: "This standard of play is fantastic. For me, the difference between the two players is that Murray is returning so well that he puts Nadal on the back foot almost every time the Spaniard serves. Murray is able to get more free points on his serve which is why I think he'll win because he can apply more consistent pressure to Nadal's game."

Murray *6-3 0-1 Nadal *denotes next to serve
Hmmm. Rafa looks angry to me - which is a good thing, I suppose. He doesn't stop scowling despite holding to love in the first game of the second set.

Pat Cash on 5 Live sports extra "Very impressive from Murray. He's just about got the right balance as far as the tactics are concerned. Whether he will win his first Grand Slam this tournament I don't know. The main thing for him was to keep Nadal off balance and that is absolutely the way to play. It has just given Nadal something to think about. Nadal will fight back here but if Murray can keep these tactics and this consistency it is Murray's match to win."

From Steveo77 on 606: "I seriously think Murray could take him here in straight sets."

FIRST SET

Murray 6-3 0-0* Nadal *denotes next to serve
Did you think this was going to be easy for Murray? You were wrong. A couple of unforced errors gift Nadal a sniff of a break at 15-30 and when the Scot is cruelly beaten at the net by a net-cord - at the end of another incredible rally - the Spaniard has two break points. Murray responds brilliantly, with two precise winners down the line on either flank hauling him to deuce and his third ace gives him a first set point. In the bag? Not yet. Nadal attacks again and Murray has to save another break-point before, finally, wrapping up the set at the third attempt. That took 53 minutes by the way - I hope you haven't got any plans for the rest of the morning...

Murray *5-3 Nadal *denotes next to serve
Murray continues to attack and continues to get his reward, fizzing another backhand winner down the line, but the Nadal serve is too strong for him this time. Still, the Scot will serve for the first set next...

jonathanhill16 on Twitter: "This is the best match of the tournament so far. Both playing some fantastic tennis. Come on Murray!"

Murray 5-2* Nadal *denotes next to serve
That's exactly the sort of game Murray needed next - an easy hold. He's mixing up the power and direction of his serve and continuing to come in when it suits him. Nadal has hardly played badly so far but he still smashes a ball away in fury at the changeover - this set is slipping away from him.

Murray *4-2 Nadal *denotes next to serve
Murray's turn to show what his forehand can do, with an absolute belter down the line taking him to 15-30. His movement around the court has been first class so far and his backhand is a bit handy too - a driven cross-court winner means we have another break on our hands - early days but it's advantage Murray at the moment.

Pat Cash on 5 Live sports extra "Murray's being forced to play the style of game he'd been chickening out on the in last year - he's being forced to come forward, and it's paying off - it'll probably pay off in this match and, if not, then in the future"

From Richard, pretending he's working in London, via text: "Dare we believe the brave Scot can slay the mighty Spaniard? It seems too much to hope for."

Murray 3-2* Nadal *denotes next to serve
The Nadal forehand takes charge in this game and, before Murray knows it, he is facing three more break-points at 0-40. Cue a change of tack by the Scot, who serve-volleys his way out of trouble and back to deuce with some smart shots. Nadal throws in a very late Hawkeye challenge to try to break up his rhythm, which doesn't impress Murray much, but it only succeeds in delaying what is a very good hold. Er, this hasn't been bad, so far, has it?

Murray *2-2 Nadal *denotes next to serve
How will Murray respond? Fighting fire with fire, that's how, attacking the Nadal serve and, helped by some sloppy play by Rafa, setting up three break-points of his own. Murray goes long on the next two points as he goes for the big return... but the Scot then finds his best shot of the match so far - a glorious top-spin lob - to break back immediately. Cue fist-pumping from Murray and a scream of 'C'mon'. Honours even again.

From intellectual_chav on 606: "First blood Nadal. Murray still warming up though. Rather tense.."

Murray 1-2* Nadal *denotes next to serve
A first show of strength from Nadal, with some brutal returns setting up two break-points at 15-40. Murray is in at the net to save the first but Nadal covers every inch of the court in the next rally before smashing away a short backhand. Sensational stuff by the Spaniard, and he has the first break of the match.

domcovkid on Twitter: "Nadal will win it in 4: Murray hasn't come up against any real threat yet. And the temperature should help Nadal."

Murray *1-1 Nadal *denotes next to serve
The outcome of this match is going to depend a lot on how Murray deals with the Nadal serve... he promised beforehand to attack it and seems to be doing just that - a rasping forehand winner takes him to 30-all. Rafa comes out on top from a lengthy baseline exchange on the next point but then shoots himself in the foot by calling Murray's next return long - Hawkeye shows it was in and we are at deuce. Still, Nadal comes through to hold - he is in at the net to put away a drop volley after another cracking rally, before throwing down a serve that is too hot for Murray to handle. All-square.

Pat Cash on 5 Live sports extra "The majority of fans would like to see Rafa go through but there is a growing group of Murray admirers throughout Australia."

Murray 1-0* Nadal *denotes next to serve
Start as you mean to go on chaps. Nadal is in at the net to take a super first point but a couple of big serves and a rolling top-spin forehand sees Murray take control. He seals his first hold with an ace. A decent start from the Scot.

0903: Here we go. Murray to serve first.

From Stuart in Beijing, via text: "Murray will start strongly, but tire himself out winning the first set. Nadal will then go on to win the next three."

0859: The scene is set - Murray and Rafa are knocking up, Rod Laver Arena is packed out, and I think there are a few noisy Scots in the house. The atmosphere won't be lacking in this one. Two minutes until we get going.

finnkjer on Twitter: "Got forced to take time off this week - too much leave - like to thank boss as in bed with you, Rafa and a brew!"

Sounds cosy!

0855: The players have just been told there will be fireworks at around 1000 GMT, probably because of Australia Day rather than any explosions on court. Still, you never know with these two...

0853: The players are out on court. Murray's colours of choice are blue and white, while Nadal goes for tangerine and neon pink. Lovely.

0851: Time for a quick interview for both players before they emerge on court. Murray says he might go for his shots a bit more today... we'll soon find out whether that actually happens. Rafa is dancing about as they wait to be introduced.

0848: Murray is singing along on his Ipod as he waits for Rafa in the bowels of Rod Laver Arena... and here comes the Spaniard now.

Gallacticos87 on Twitter: "Murray in straight sets. As a Scotsman, I fully expect him to do brilliantly in this match and blow it against Cilic..."

0846: Ricky Hatton is already in his seat on Rod Laver Arena, and it can't be long before Murray and Nadal appear out on court. Hopefully.

0841: Not long to go now folks. Excited? Me too. The 606 boards don't open until 0900 GMT but you can text me your thoughts using the numbers above or tweet me some, er, tweets, on Twitter. Go on, please.

From Ali in Birmingham, via text: "This has all the hall marks of a five-set epic! I'm sure Federer would love to see these guys burn each other out."

0836: Give this page another cheeky update and you will see our live stream from Rod Laver Arena appear at the top as if by magic, for UK users only I'm afraid.

0833: So, who's your money on this morning? Murray has been in fantastic form so far in Melbourne, while some doubts remain over whether Rafa has returned to the very top of his game following his injury problems in 2009. The Spaniard has lost 10 of his last 11 matches against fellow top-10 players too. Time to find out what both men are made of, I suppose.

0827: Andy Murray on Rafael Nadal, who has won seven of their nine previous meetings: "I think I can win. I think I've got some tactics that work well against him. I'm playing well."

0825: Rafael Nadal on Andy Murray, the only man to reach the last eight of this year's Australian Open without dropping a set: "Playing Andy is one of the toughest matches you can have on the circuit. To beat him you have to fight at every single moment and then see what happens. He can play every single shot well. He serves very well. He can play defence, he can attack, he has good hands. He uses his sliced backhand very well and he's able to change his hands very quickly to play drop shots. He has a lot of options in his game and that's a big advantage."

0818: As Piers told you before he shuffled out of the door, Murray-Nadal has been put back a few minutes to 0840 GMT... That's the only bad news, though, because it will be live on BBC Two, BBC HD, this website and 5 live sports extra. I ask only one thing from you in return and that is to give this page a manual refresh... just so my name appears at the top. I'm sure you understand.

0814: Morning all. Piers looks like a man who needs his bed, while I am refreshed from a night dreaming of a famous Andy Murray victory. Hold on to your hats folks, this should be very special indeed.

0810: Right, Andy Murray v Rafael Nadal coming up at 0840 GMT, slightly later than planned because of the five-setter we've just witnessed. I require recharging so will leave you in the capable hands of Chris Bevan, who will tell you about the many ways you can enjoy the match.

0802: Marin Cilic: "It wasn't easy, I just got a few extra gears in that last set. It wasn't easy when he was putting a lot of pressure on my serve and I didn't know what to do."

0758: Fourteenth seed Marin Cilic of Croatia beats seventh seed Andy Roddick 7-6 (7-4) 6-3 3-6 2-6 6-3 to reach his first Grand Slam semi-final, where he will play Andy Murray or Rafael Nadal.

0754: Roddick races through a quick service game and we'll see if Cilic can finish this one off.
Fifth set: Roddick 3-5 Cilic

0751: Cilic sweeps a majestic backhand down the line for 40-30 but needs a couple of deuces before holding serve with an ace.
Fifth set: Roddick 2-5 Cilic

0745: Roddick is creaking under the pressure but just about hangs onto his serve to keep his hopes alive.
Fifth set: Roddick 2-4 Cilic

0739: Cilic holds his nerve under huge pressure at deuce with two thumping aces and a first Grand Slam semi-final beckons.
Fifth set: Roddick 1-4 Cilic

0733: Cilic makes the breakthrough, moving Roddick around brilliantly to get to 0-40 and converting his second when the American pulls a forehand into the tramlines.
Fifth set: Roddick 1-3 Cilic

Greg Rusedski on Twitter: "what a match cilic/roddick. cilic has advantage serving first in 5th, but roddick has more experience in this situation. still sticking w arod."

0728: Cilic fires a forehand winner onto the line for 40-30 and sticks away a smash on game point.
Fifth set: Roddick 1-2 Cilic

0721: A huge chance for Roddick with 0-40 at the start of the fifth set but Cilic hits two big serves and a winning forehand to come through.

0718: Laura Robson on her decision to pull out of the girls' doubles with Heather Watson after making progress in the senior doubles: "We all thought it was the right decision, that it would be too much. I didn't say it to her, I felt so bad so my coach did. It was his decision more than anyone else so I'm going to put the blame on him. I felt really bad for Heather."

0713: Roddick frames a straightforward mid-court forehand for 30-30, but the seventh seed finds two big serves to take us into a fifth set.

0707: This strange match rumbles on. Roddick appears set to flush out my seventh seed digs deep to find a couple of nby hit the heights in terms of sustained quality but it's been quite a comeback from Roddick.

0656: Cilic has gone right off the boil and Roddick breaks again to lead 3-0 in the fourth set.

0649: The fightback is well and truly on as Roddick breaks at the start of the fourth set when a nervous looking Cilic puts a backhand wide.

0647: A first reminder of the morning that Andy Murray v Rafael Nadal will be live on BBC Two, BBC HD, the website and 5 live sports extra from 0830 GMT. And the schedule for Wednesday is in, with Djokovic v Tsonga the red button match at 0830 GMT, which means you'll have to stick with me for Federer v Davydenko and the Williams sisters overnight.

0642: After a brief quibble with the umpire over a net cord call on a serve, Roddick wraps up the third set. Cilic leads 7-6 6-3 3-6.

5 live's Jonathan Overend on Twitter: "Done the practice courts.. Nadal is on Court 16 hitting with Aussie junior Sean Berman. Huge crowds, one flag saying 'I love Uncle Toni'. Murray is out on Court 4 hitting with Thomas Muster, the former French Open Champion who lives much of the year here in Oz..."

Greg Rusedski on Twitter: "Morning, a lot of different picks for nadal and murray sent in. That what makes it such a good match to watch. 51/49 murray/nadal."

0635: Roddick is looking fairly comfortable at the moment and the crowd on Rod Laver Arena are certainly behind him as he closes in on the third set at 5-2.

0626: Look out ladies, Henri Leconte and Pat Rafter have teamed up for the legends' doubles against the Woodies on Margaret Court Arena. Henri's gallic charm, Pat's Aussie... charm. Unstoppable. Cilic stops the rot and trails 3-1 in the third.

0623: Cilic misses the kind of high backhand volley that could give Roddick some nasty Wimbledon flashbacks, but the American converts his second break point in game two and soon finds himself 3-0 up the third set. It's a long way back but...

0614: Britain's Tom Allen and Jack Carpenter beat Averfalk and Toledo 6-2 6-2 in round two of the boys' doubles. It's been a good day for the Brits. So far.

0608: Cilic serves out the set confidently and he leads 7-6 6-3, while British boys Tom Allen and Jack Carpenter are closing on victory in the boys' doubles out on Court 11.

0605: "I really hope murray performs... I convinced my friend to stay up all night and he looks angry."
Theo, london, via text

0602: Maybe the game isn't up after all. Roddick manages to get a couple of break-back points but Cilic sees them off and leads 5-2. Roddick is still fighting though.

0554: The game appears to be up for Roddick when a sliced backhand gives Cilic two break points, and the Croat converts the first with a neat sliced backhand down the line. Roddick looks a pretty forlorn character right now, and it's 7-6 4-2 for Cilic.

0549: Roddick immediately gives his service break advantage back and it's 2-2 in the second set. Cilic then nearly does for a line judge when chasing down a ball and does well to hurdle the startled official. He recovers from 0-30 to lead 3-2 and the trainer is back yet again for Roddick.

0541: Britain's Laura Robson reels off five games in a row to beat 11th seed Yulia Putintseva of Russia 6-2 3-6 6-2 on Court 3. Huzzah! I have just thrown my hat in the air.

0539: Possibly as a result of his injury worries, Roddick starts to play a bit more aggressively and it pays off as Cilic nets a defensive backhand to drop serve. Roddick leads 2-1 in the second set and then heads for another massage.

0535: "Have woken early & am preparing for an interview later this morning. The question is what is the latest I can leave home so that i can watch as much of murray as possible. Thank goodness for live text, so i can check the score until i go in. Go Murray!"
Katie, Kent, via text

0535: "Hard work being a brit in america keeping up with tennis in oz! Time zone crazy!"
Yvonne, in Reston virginia, via text

0533: Robson breaks Putintseva to lead 4-2 in the final set and a national crisis may have been averted.

0530: Roddick returns to action fairly gingerly and Cilic wastes little time in holding his opening service game of the second set.

0525: Roddick has his shirt off and is getting a vigorous neck massage, which is exactly what I could do with, while Cilic wanders around in the shade of the court. Robson has broken back for 2-2 against Putintseva. I'm getting better at spelling her name at least.

0520: Roddick calls for the trainer....

0519: Roddick smacks an inviting return into the tramlines and it's two set points for Cilic.... a long rally ensues and Cilic finishes it with a rasping forehand down the line. And I don't know how to tell you this but... Robson has been broken. She trails 2-1 in the decider.

0514: Roddick and Cilic change round at 3-3 in the tie-break and both men are having their dodgy moments. Putintseva and Robson are 1-1 in the decider.

0455: "Eric in colchester, you will be crying in your cornflakes my little spanish boy never lets me down."
Nigel in brent knoll, nadals number 1 fan, via text

0511: "Laura Robson has just dropped a set? That can't be right, it must be a mistake surely."
Al, London, via text

0509: Roddick gets to 0-30 up and then plays two really poor points, but Cilic helps him out with a double-fault and a wild forehand to hand the break straight back - tie-break.

0503: Clever stuff at the net from Cilic fashions two breaks points and Roddick misses with a straightforward forehand. Cilic leads 6-5 and will serve for the set. Meanwhile, Putintseva has levelled at one set all against Robson and a national emergency looms. Is Gordon Brown up at this time? He should be informed.

0458: We're at 30-30 on the Cilic serve and the Croat misses the chance to put away a forehand into a gaping court. Set point Roddick... but Cilic saves it with a forehand that the American cannot get to effectively and it's 5-5.

0455: "I have been enjoying the tennis so much ive actually started sleeping during the day so im awake for the tennis at night!"
Taran, the netherlands, via text

0455: "Nigel in brent knoll will be sorry when murray wins in 4 sets."
eric in colchester... Murrays number 1 fan... via text

0453: Roddick is generally on the back foot here and he faces another break point but smacks a big serve to get out of trouble. The American leads 5-4 but is playing very passively. And Robson has the break back to trail 3-2.

0447: Cilic and Roddick have a battle of the backhand slices at 30-30 in game eight, with Roddick eventually catching the tape, and the man from Medjugorje makes it 4-4. And hang on, Putintseva has broken Robson to lead 3-1 in their second set. That's not really on.

0437: A couple of regulation service games take Roddick and Cilic to 3-3, the Croat just edging it so far, while Putintseva wins a lengthy opening service game at the start of her second set against Robson.

Elena Baltacha on Twitter: "Morning all, have been up since 3am..loving the jetlag! watching aus open!! anyone else watching the tennis? x"

GCChristie on Twitter: "I don't have to worry about falling asleep as I'm over in China, but, hopefully I can finish work in time to see Murray."

0429: Cilic nets a backhand to set up a break point for Roddick, but the Croat finds a big-serve big-forehand combination to hold on and it's 2-2.

0427: Robson seals the opening set 6-2. For those of you keen to get the inside track on Yulia Putintseva, I can tell you that she is actually younger than Robson, which hardly seems possible. She claims to be 15, hail from Moscow, like clay, shopping and going to the movies. A likely story.

0424: Laura Robson breaks serve again and leads her Russian opponent, whose name I'm having great difficulty with, 5-2.

0422: Cilic is happy to rally with Roddick and gets an early break-point chance but plays a loose forehand. Cilic attacks again with the forehand and earns a second break point... but nets a backhand after working the opening. A third break point goes begging with a backhand error and Roddick comes through a strange game - passive from the American, sloppy from the Croat.

0418: "So instead of just going to bed at 12 in order to get up for the murray match, i started watching the other matches, its now past 4, may as well just all night it, seriously need to sort my life out."
From danny k via text

0417: "I wont get home from work til 0930, so i will miss nadal triumph in straight sets."
Nigel in brent knoll via text

0416: Justine Henin on making the semi-finals: "I'm here again in the last four but there's still a long way to go. I'll just try to be focused on what I have to do on the court and hope it keeps going this way. I'll have good recovery and two good nights. That's what I need. But it's just a great feeling to be in the semis of the first Grand Slam since I'm back."

0413: Cilic responds with an equally impressive service game for 1-1 and Robson is 3-1 up. All is well.

0409: Roddick does not exactly look a bundle of nerves as he wallops down three massive serves on his way to 40-0, bunts a backhand volley long but takes the game moments later. And Robson leads 2-1 with a break on Court 3.

0403: Britain's Laura Robson is now in action on Court 3 against 11th seed Yulia Putintseva of Russia in round two of the girls' singles. Robson isn't seeded as she spends more of her time on the ITF and WTA circuits these days, but at 16 she's still younger than many of the juniors. And she breaks in game one to lead 1-0.

0400: "This is the only thing keeping me going. So I hope you publish this text. Question is do I stay up to see Murray Mint once my shift is over? Let the public decide!"
From a tired paramedic in Waterloo via text

0353: The next match on Rod Laver Arena should be a good one - Andy Roddick v Marin Cilic, with the winner to play Murray or Nadal in the semis. The pair have a 1-1 head-to-head record and both played five-set matches in the previous round.

0348: China's Jie Zheng beats Maria Kirilenko 6-1 6-3 when the Russian double-faults on match point to set up a semi-final against Justine Henin. And Arthur 'stop giving me grief' de Greef appears to have exited Court 3, so we could be ready for Laura Robson.

0343: Kirilenko is a decent doubles player and, with her dodgy leg/hip, is throwing caution to the wind and coming in a lot more now, but it might be too late. Zheng fires a backhand winner past her at the net and holds for 6-1 5-3.

0335: Zheng has a bit of a moan when she's not allowed to go to hawkeye because she played on, and an inspired Kirilenko smacks away a backhand return to go 0-40 and earn three break points.... Kirilenko nets on the first, Zheng gets a lucky net cord on the second, Kirilenko misses a return on the third. A fourth chance arrives but Kirilenko dumps a poor forehand return into the net and Zheng holds for 4-2. That could be that. And look, I've started a photo gallery. Lovely, innit?

nikkwoodward on Twitter: "great tennis, beautiful weather, cool enough under shade of roof, pesky red arrows a tad distracting!"

0323: Amid the constant buzzing of planes and the trials and tribulations of her opponent, Zheng is playing very well and she leads 6-1 3-1. And, no, we do not have a Jack Duckworth or a Billy Mitchell playing in the boys' juniors, to those who asked. Really...

5 live's Steve Rudge on Twitter: "Update on Vega 91.5's all time rock legend 500 countdown being played around the grounds. Now at number 62: Coldplay - Viva la Vida."

0317: Well played. Kirilenko steels herself to hold serve with some more aggressive hitting behind the serve, but the trainer is on again at the changeover and the Russian will do well to finish this.

0314: "Just fallen asleep on the night bus and ended up on the edge of London. Can you bring the Murray match forward to keep me awake please. Thanks."
Will, cold, muswell hill/London via text
As a regular bus snoozer, I salute you. But no, I can't.

0314: "Man, its not good what u are doing. U'v not posted any contributions from the African continent! We also follow tennis and surely nadal wins today!"
From Vyash, Mauritius, via text

0311: You've got to feel a bit sorry for Kirilenko, playing in her first Grand Slam quarter-final, as she is clearly struggling physically, is spooked when preparing to serve by a very low fly-by as part of the Australia Day celebrations, and there is someone in Zheng camp cheering the Chinese player's every move very loudly. Zheng leads by a set and 1-0 with the break.

0305: OK, bit of a lengthy break there as Kirilenko had treatment to her leg and she's not moving that well on the resumption.

MarkRobMatthews on Twitter: "there is a J Duckworth playing over on court 7 in the boys singles..please tell me his first name is Jack? lol Thx"
Bad news I'm afraid, he's a James.

0257: Zheng wraps up an excellent first set 6-1 in 34 minutes and gives it some "Come on!" Kirilenko calls for the trainer. Meanwhile, Arthur de Greef is taken to a final set, allowing us all to enjoy his name a little longer but delaying the arrival of Laura Robson.

0254: Kirilenko is being roundly outplayed from the back of the court and makes the excellent move of serve-volleying to save a first break point, but Zheng is fired up and attacks the serve to convert her second. The Chinese player made the Wimbledon semis a couple of years ago and looks highly likely to at least equal that feat.

0245: There we have it, Britain's Oliver Golding beats Sam Barry of Ireland 6-7 (8-10) 6-3 6-4 in the second round of the boys' singles. Laura Robson should be starting on Court 3 within half an hour or so.

0244: Zheng saves a break point and moves 4-1 clear of Kirilenko. It looks fiercely hot out there, I think we're better off over here. Honest.

0241: "Hate to be so Scottish about this but can more people please start saying Nadal is going to win, generations of sportsmen have proved we're rubbish when favoured but a mighty underdog."
Kieran in Glasgow via text

0238: Kirilenko lets out a scream when she succumbs to a barrage of Zheng groundstrokes and falls 15-40 down. The Russian then sends a forehand wide and it's 3-1 to Zheng. And comeback kid Barry has one of the breaks back to trail Golding 5-3 in the decider. Squeaky bum time for the Brit.

0232: Zheng hoists a perfect lob over the stranded Kirilenko to make it 2-1 on serve, while Golding gets the double break and will serve for the match at 5-2 in the final set against Barry.

0225: Piero, Peas... where's the respect? In answer to your questions, I will be battling my way across London before settling down on the sofa to watch Murray v Nadal and promptly falling asleep; and apparently it costs a lot of money to show live TV coverage and there is not quite the audience to justify it at 0225 GMT. I'm told.

0223: Zheng opens the second quarter-final with a solid service game to lead 1-0.

0221: "Lovin ur live txt Peas (we've nicknamed you Peas) waiting for Handy Murray with my BFFs red wine and chocolate and flatmates Rob (Jockstrap) and Hot Wendy... uni at 12 so whats the chances of straight sets? keep it up xxx"
Hannah, Manchester, via text

0218: "Piers are you working the Murray Nadal match too? It's a hard one to call, I am going for Murray to win 6-4 in fifth set."
From Moose in Bermuda via text

0218: "Much as i love your outstanding banter, piero, why can our license fee not afford actual footage?"
Toby strutt in kennington via text

0217: Next up on Rod Laver Arena we have Sharapova-conqueror Maria Kirilenko of Russia against China's Jie Zheng, for the right to face Henin in the semis. Zheng has a 3-0 record in head-to-head meetings and Kirilenko is making her Grand Slam quarter-final debut, while Zheng made the last eight at Wimbledon in 2008.

0206: While all that excitement was happening on Rod Laver Arena, Oliver Golding levelled at one set all against Sam Barry on Court 5.

0204: Todd Woodbridge asks Henin if she would prefer to play Jie Zheng or Maria Kirilenko next. Not surprisingly, she says "both will be extremely difficult". Just once I'd like a player to say, "definitely Zheng/Kirilenko, she's absolutely useless. I'll thrash her."

pwalker32 on Twitter: "Inspired by Justine:doing some air one handed backhands down the line with some fade while swotting up for interview on Fri."

0201: Henin makes her move at 30-30, hooking a fantastic forehand winner cross-court for match point... and Petrova sends a backhand long. Justine Henin beats Nadia Petrova 7-6 (7-3) 7-5. Oh Lordy, an on-court interview...

0157: "What a match here on court 5, the Irish kid can really play ..great game for the future .. Set up and 4-3 down against golding, the fighting Irish."
Kevin via text

0157: "Stuck in A&E after a football accident 5 hours in and this feed is getting me through the pain."
Graham, Urgent Care Centre, London via text
We are the fifth emergency service.

0156: Where have these two been for the last two hours? Henin plays an absolutely beauty of a backhand down the line and holds to love, so Petrova will again serve to stay in the match.

0153: Now Petrova steps up her game and finds a love-service game from nowhere to make it 5-5.

0152: Thanks everyone for filling me in on the life and works of Jessica McNamee, I feel like I know her now. Here's hoping she enjoys her day at Melbourne Park.

0150: Some properly good tennis, at last, gives Henin a quick love hold and she's one game away now at a set and 5-4 up.

0148: Juniors Barry and Golding continue to battle away on Court 5, with Barry breaking back to trail 4-3 in the second set having taken the first. And fellow junior Arthur de Greef of Belgium is in pole position for today's 'best name in the juniors' prize.

0147: One ugly rally sums up this match - Henin totally mishits a lob that barely makes it to the net, only for Petrova to frame her smash into the net. The crowd stifles a laugh. It's soon break point for Henin.... and Petrova hangs on by the skin of her teeth as Hawkeye shows her second serve to have grazed the back of the line. The Russian makes it 4-4 in the second set.

0142: Henin finds a bit of form and takes her fourth straight game to lead 4-3, although only after putting a drive-volley into the net on her first game point. Roddick v Cilic will be on after Kirilenko v Zheng, which follows this. I'm guessing around 0400 GMT. I'll be here.

0141: "McNamee was also in Home and Away but not sure who she played as I was more of a Neighbours fan myself. Also when's Roddick on court? Before or after Murray?"
From anon via text

0140: "Well i've googled ms mcnamee and she's best known 4 her role in "packed to the rafters" - a fly on the wall about pat?"
From Jane via text

0138: Henin has the chance to level the set with another break point but goes for too much on a return. The former world number one recovers with a magnificent forehand cross-court winner on the run but misses with a return on her second break point of the game. Petrova then saves a third with an ace - yes, an ace - but thumps a forehand long on the fourth and it's 3-3.

Gallacticos87 on Twitter: "People are expecting Henin to do a NY-Clijsters, and so their standards are v high for her. Unfair, that was a total one-off!"

0128: "Drazic's (Mulvey) at the tennis?! What a babe. I totally fancied him when I was 16! Btw Rafa to win in four."
From anon (very sensibly) via text

0125: Henin always has a chance here as Petrova's scond serve is pretty dire, and the Belgian gets one of the breaks back to trail 3-1. Information is flooding in all the time about Callan Mulvey, by the way. Less so on Jessica McNamee.

0119: Ireland's Sam Barry is clearly made of stern stuff. He recovers from 5-1 down in the set and 6-3 down in the tie-break to take the first set 7-6 (10-8) against Britain's Oliver Golding. And Petrova gets the double-break for 3-0 in the second set against a struggling Henin.

0116: "Struggling to stay awake but enjoying your coverage. Sounds like Petrova & Henin are sleepier than I am but Justine seems to wake up on the big points. C'mon Juju!"
From Fungai in Ipswich, Suffolk, via text

0115: "Hey Piers, its great that you're keeping an eye on the juniors too. Sorry, but it would be great for irish tennis if sam barry does well! Come on sam!"
Eoin, ireland, via text

0110: Petrova gets stuck into the Henin serve at the start of the second set and earns two break points at 15-40. The first she buries in the bottom of the net, the second just catches the tape, but another chance arrives soon enough and Petrova takes it with a decent return. It's hard going for everyone, this.

0107: "In response to 0039 who is callan mulvey? Only my favourite ever aussi actor from classic 90s school drama heartbreak high. So good he was he appeared in home and away years later."
From anon (very sensibly) via text

0104: It is the turn of Petrova to play like a drain in the tie-break, endangering the line judges with some of her groundstrokes, and Henin is quickly to 6-1. She lets a couple of set points slip by but takes the third with a rasping cross-court backhand winner. Barry and Golding into their own tie-break on Court 5.

0058: After losing four games on the spin, Henin does not look a good bet to force the tie-break but in fact she comes up with a decent service game and it's 6-6. And Sam Barry now leads Oliver Golding 6-5 on Court 5.

0054: Petrova hits an ace down the 'T' for 40-15 and I nearly fall off my chair in shock. She then hits another one to take the game and lead 6-5, but this time I remain firmly seated.

0050: The pattern continues on Laver, with Henin double-faulting to go 0-30 and Petrova seemingly firing a return winner before HawkEye says otherwise. It's a momentary let-off for the Belgian but she soon slices a backhand into the middle of the net and it's 5-5. You know what I said earlier about the best backhand ever? That wasn't it. Ireland's Sam Barry is on the comeback trail on Court 5, pegging Oliver Golding back to 5-4.

0045: Yuk. This match has been of a surprisingly poor standard so far, and this time it's Petrova who is all over the shop. She pulls a forehand wide and then plays a howler of a volley, before Henin gets the break for 5-4 by attacking another tame serve. And I fancy Murray in four.

0044: "I'm here, Piers! Is this definitely the same Petrova? The one that served 5 aces and no double faults against Clijsters? Meanwhile, allez Justine!"
SKim via text

SaroopChana on Twitter: "whats your prediction for murray vs nadal match?.....for me it depends on who wins the 1st set....hopefullly its murray."

0042: Henin plays a wild shot over the baseline to fall 15-40 down and another error gives back the break - 4-4. A very strange game from the Belgian, who has shown the odd sign of nerves since returning to the sport this month.

0039: Petrova gets back on track with a decent service game but still trails Henin 4-3. It is Australia Day in... Australia. My congratulations to everyone down under. To mark this prestigious occasion they've pulled out all the stops with the celebs on show at Melbourne Park. I have honestly never heard of any of them. Jessica McNamee anyone? How about Callan Mulvey?

0035: Henin holds with ease for 4-2 and Petrova needs to get a grip of this or it could be over quickly. Out on Court 5, Britain's Oliver Golding leads Sam Barry of Ireland 5-1.

0031: After a couple of Petrova double-faults, Henin climbs all over a service return at 30-30 and follows it into the net to put away a volley. It's break point and... another double-fault. The Belgian leads 3-2 with a break. What is it with everyone's serving at the moment?

0027: Henin holds for 2-2, and this match is yet to catch fire. There appear to be numerous people who are going to bed in order to be 'fresh' for the morning. I can't say I'm not disappointed, even a little hurt.

0023: "I hope you don't mind me missing out on your live text by catching up on some sleep before Murray beats Nadal in 4 sets this morning? Thanks Piers, you're a gent! "
Sean, Aberdeen , via text

Victoria Azarenka on Twitter: "just woke up without alarm:) amazing lol...gonna go for breakfast now and maybe sleep more:) thanks for all the messages! i appreciated it."

0021: We get the first "Allez!" of the day as Henin gets to 30-30 and Petrova then double-faults to face break point... but the Russian hangs on with some heavy groundstrokes behind her serve and holds for 2-1 thanks to a HawkEye challenge.

0020: I feel it is my duty to keep tabs on you throughout the night and check that you haven't nodded off, so please make regular contact through Twitter or via text on 81111 (UK) and +44 7786200666 (worldwide).

0017: Henin holds to love for 1-1, slicing one ace out wide along the way. Out on Court 5 we have Britain's Oliver Golding against Sam Barry of Ireland in the boys' singles, with Laura Robson up against Yulia Putintseva in the third match on Court 3.

0013: Petrova serves first, and holds from deuce.... Henin carries a 12-2 head-to-head record into the match and she beat the Russian in Brisbane earlier this month in her first match back after retirement. However, Petrova stunned pretty much everyone by thrashing Kim Clisters 6-0 6-1 in the third round in Melbourne and followed that up with victory over third seed Svetlana Kuznetsova.

0009: Deliberately thrown my sleep pattern out of sync by sleeping all day and just getting up now. Sitting here with my cereal looking forward to a great day/ night of tennis!"
From Ali, Glasgow, via text

0007: So first up is the best backhand in tennis history. Fact. Well, alright then, it's subjective but it's certainly my favourite and I'm in charge, right? It might not be enough for Henin today though, as Petrova looks in the mood to shed the 'underachiever' tag after beating Clijsters and Kuznetsova in her last two matches. That means you're very good. They're not hanging around today, with Henin and Petrova already getting stuck into their knock-up on Rod Laver Arena.

0003: As is now traditional four times a year, I have spent the day fielding texts, tweets and emails from people with a sudden interest in tennis. I wouldn't mind but I was trying to sleep. Anyway, we know the drill here - Andy Murray v Rafael Nadal will be live on BBC Two, the website and 5 live sports extra from 0830 GMT.

0000: Some might say that the next few hours are a mere appetiser for what is to follow, but some would be wrong. In fact, who do some think they are? We're about to see if Justine Henin can continue her bid for a comeback Grand Slam title when she takes on the extremely in-form Nadia Petrova, followed by, er, Jie Zheng v Maria Kirilenko, and then a rejuvenated Andy Roddick against man-on-the-verge Marin Ciilic. And there's Laura Robson in round two of the girls' singles too. Flippin' some.

2356: Evening chaps. Look sharp, there's a bit of a 'do' going on tomorrow morning and we need to get in the mood. It's still eight hours until Andy Murray takes on Rafael Nadal in the quarter-finals of the Australian Open, I suggest we huddle together and make the best of it.