2242: So it's all about Group B tomorrow. The mighty Piers Newbery is back in the O2 hood tomorrow. Federer v Soderling from 1400 GMT. Murray v Ferrer from 2000 GMT. Thanks for all your comments today. A strange old day. Let's all do a little dance in honour of Novak's right eye. The game needs that boy. Don't forget Rafa though - he stayed cool during quite a testing time tonight. And sleep well Muzza. A big old day for you tomorrow. Sleep well folks. Time to start thinking about the Ashes isn't it? Now where's that coffee?... night.

2235: I'll be wrapping up shortly, but I'll be available on twitter for any further nonsense and tennis analysis you wish to engage with me on. Plus for all the latest news from the O2 then check out tweets from our man David Ornstein or the team from BBC Radio 5 live.

jjjlee1988 on Twitter: "Gosh isn't Djoko a star? Signing autographs even though he must be gutted to lose after playing quite well..."

2228: Just a reminder on the table permutations. If players finish after three matches level on wins, it goes down to the following priorities: 1) head-to-head 2) % of sets won 3) % of games won. The event organiser comes out and explains that Djokovic was struggling after putting the contact lens in correctly the second time. He suggests the lens may have just dried out or he had something behind it. Not the most definitive of answers but those are the facts we have.

2223: Nadal is beaming like a cat. Do cats smile? Which animals are the best smilers? Enough. Nadal says: "It was a very good match for me. I'm very sorry for Novak - I wish him all the best for his eyes. This was my best match in London. I'm very happy - the first 10 games were very level but I'm just very happy with the two victories."

2219: Overall thoughts? Djoko wanders off court with head bowed low. What a shame. Nadal still not guaranteed his progression but he plays Berdych on Friday night. Tomorrow's games - Federer vs Soderling in the afternoon. Murray v Ferrer Thursday evening.

Ryan in Southampton, via text 81111: " Does Djoko have a pair of specs in his locker room?? May be a good idea to carry in future."

Djokovic* 5-7 2-6 Nadal
Djoko's comeback begins. The first point anyway. Nadal nabs the next two points and the crowd shout out in desperation trying to lift the Serb. Another ace and it's two match points for Nadal. And there it is. NADAL WINS. Match win number two of the week for Nadal.

Djokovic 5-7 2-5 *Nadal
Djoko survives for a few more minutes with a comfortable service game.

Djokovic* 5-7 1-5 Nadal
Djoko pulls back the trigger and plays a remarkable winner that lands in the corner. 32 more of those Novak and we might have a game on our hands. Both players cranking up the grunt levels and Nadal somehow gets it to 40-30 with Djoko standing tall at the net and unable to smash home the winner. The world number takes the game with a smash from the back of the court. Just a few minutes away now. This would be the greatest comeback since the return of the dinosaur which hasn't quite happened yet - as far as I know - unless someone has seen one out there?

sssssarah on Twitter: "Sad inevitability about this now, it's why Djokovic needed to win the first set."

Djokovic 5-7 1-4 *Nadal
Djoko affords a smile as he takes a 30-15 lead and with Nadal taking his Spanish feet off the gas, Novak gets one on the board thanks to an ace. Big cheers and Djoko raises his hands in appreciation. Phew, no bagel.

Djokovic* 5-7 0-4 Nadal
It's unfortunately looking a little routine for Nadal now. Djoko plays with his strings but I don't think it's your racquet Novak old boy. Shame. This match started brilliantly. And polite applause rings round the O2 as Nadal grabs a four-game lead. Anybody out there play sport with contacts for their eyes have any advice for Novak?

Djokovic 5-7 0-3 *Nadal
Forget Djoko's eye, Nadal is still on fire. He rolls into a 0-40 lead (thank you for your text by the way James) and then crashes home a stunning winner for his second break of the set and he'll be dreaming of the locker room and his favourite restaurant in west London very shortly. David Bowie's Let's Dance booms out. Djoko could do with a bit of dancing round the net right now.

Max in London, via text 81111: "At O2 watching the tennis Djokovic is wearing the worst outfit ever seen since miami vice."
Are you kidding? There was nothing but fashion feasts in the mighty Vice. I based half of my wardrobe on Don Johnson (or Crockett). I'll stop right now before I look like a buffoon. I fear it may be too late.

Djokovic* 5-7 0-2 Nadal
The two opening points are shared and thankfully (he says with fingers and legs crossed) Djoko is looking a little more comfortable. It's 30-30 and Djoko has a sniff but he wades into the net a little half-heartedly and Nadal has an easy pass. Commentator reveals that Djoko's problem is being treated as an "equipment" problem - not medical - and that's why he's been given the extra time. Nadal wraps it up though and he's showing no sympathy to his opponent.

Djokovic 5-7 0-1 *Nadal
Djoko's head is bowed as he does his best to focus on the tennis. Nadal's forehand is showing Djoko no mercy as a number of missiles are hurled back in Djoko's direction. Three break points already. Massive shame and it's game over as Djoko comes into the net and plays it long.

2145: Nadal is prowling the court looking disgruntled while the Gorillaz play in the background as the trainer or eye doctor - or whoever - is shining a mini-torch thing into Djoko's right eye. Here we go again. Set two.

Djokovic* 5-7 Nadal
Nadal is a master at creating angles with his shots but Djoko is hanging in there and takes the first point. Djoko squints and he looks a little uncomfortable. Hope that eye lens has calmed down. Djoko fumbles with his right eye immediately after playing a sloppy one 20 feet wide of the line. 15-15. Djoko definitely not happy and he plays another one long. Very long. Great rally and Djoko makes it 30-30 after finally getting success with a dropshot. Brave. Like it. Hello, hello, guten tag. A mis-hit sends a loopy one back to Nadal and it works! He's got a break point. Wasted though as Djoko plays into the net. The crowd sound distraught. Deuce and then Nadal's forehand saves him again. Now on to their third deuce. Can you feel the tension out there? Nadal has his first set point as Djoko goes very long. A bruising first set ends with Djoko forcing one into the net. 75 minutes of drama. Ready for a long one? What would you say to Djoko if you were his coach?

Djokovic 5-6 *Nadal
Here's a chink of light for the Spaniard. He leads 30-15 and Djoko is taking his time. Tension fills the O2. OOOf. A double-fault later and it's two break points for Nadal. Has Djoko just lost his bottle? Djoko goes long and it's a second break for Nadal - a chance to serve for the first set. The momentum has taken a slight shift. But I know you know that.

Djokovic* 5-5 Nadal
Two big serves, a winner from the net and it's soon level again. Not too many cracks in these boys' games. I'm still fancying Nadal but this is tight. What do you reckon? Should Djoko have a shave? Joking apart, what are your thoughts on the tactics seen so far?

Caleb in Nigeria, via text 81111: "Djokovic seems to be playing better tennis at the moment, but you can never under-estimate Rafa, except at your own peril. Be prepared for a long night"
Wise words.

Djokovic 5-4 *Nadal
No worries so far. An ace takes Djoko to 40-0 and Nadal sends one wide to hand Djoko an easy service game. Tim Henman would now say we were at the "business end" of things.

2119: Djoko comes bounding back. He apologises to Rafa and he's back on it. Time for him to serve. Let's hope he can see the ball.

jonjaulee1988 on Twitter: "Only thing keeping me sane during/after exams today was the prospect of Nadal vs Djokovic tonight... Cracking match so far."
Keep your thoughts coming in. Apologies if some of my words appear to be appealing to a five-year-old audience. The 5-year-old football fan sitting next to me is loving it.

Djokovic* 4-4 Nadal
Djoko returns 15-0 down and he's still having problems with his eye. Nothing his eyes would have done with that extraordinary forehand from Nadal - he was two feet off the ground when he belted that one back and it's game to love. But Djoko then rushes off the court to go sort his pork pies out. (Sorry eyes) Time for the O2 to crank up the tunes. Can't quite hear the tune but I've got a horrible feeling it's Meatloaf. Tell me my ears are deceiving me please.

2111: Djoko takes a bit of time-out as he's having a few problems with a contact lens. I think everybody needs a break after this opening seven games. Back going again.

bexizod on Twitter: "Saw Rafa beat Roddick on Monday live at the O2. Now back home hoping he beats Djokovic!! Though feel Djokovic may win this 1!"

Djokovic 4-3 *Nadal
Mr topsy-turvy is dishing it out again with Djoko struggling on his serve. 30-30 and a stunning curling forehand on the run that lands inside the baseline gives Nadal a break point. Djoko winds his forehand up and it's deuce. Both players are at the top of their game. Who says this is just an end-of-season hurrah? They want this. 3-3. 40-40. Tense, level and utterly compelling. And Djoko survives as Nadal sends a return long.

Djokovic* 3-3 Nadal
Nadal's turn to wobble as he trails 0-30 on his serve. Nadal gets one back but Djoko looks very very determined as he hammers a back-hand down the line. 15-40 - two chances for Djoko to bite right back and Nadal looks like an amateur as he blazes wide - game on again. Great response from Djoko.

Allie in Kent, via text 81111: "Early thoughts?! I love Novak! So naturally he should win, but he does need a shave! Not sure i like round robin, too confusing to figure out how to determine who goes through!"
If matches won are level - priority given to: 1) Head-to-head 2) % of sets won 3) % of games won. Easy huh?

Djokovic 2-3 *Nadal
Shot of the match so far by Nadal. Djoko comes in short but Nadal winds up his back-hand and boom - brilliant. Gets it back to 15-15. Nadal plays a wonderful looping shot from the baseline that lands at Djoko's feet at the net. Not a chance for the Serb. Another corker from Nadal and he has a break point. A high looping forehand has Nadal struggling and it's deucey time. Big fist-clench from Djokovic. Both players using every inch of this court as Djoko goes wide. Another break point and another and Nadal wins it as both play pitter-patter at the net. Stunning and the crowd love it. So does a certain man in a headband. The crucial breakthrough?

Djokovic* 2-2 Nadal
Djoko grabs the initiative at the net and makes it 15-15 with a nice back-hand volley combo. Brilliant defence from Djoko but Nadal does enough as he takes the chance to prowl at the net. Match back level again. Early thoughts?

Anonymous, via text 81111: "Re 2002 entry. That's not entirely true. If Djokovic wins today he's definitely through but Nadal winning still leaves the possibility of 3 players finishing with 4 points and then anyone can go out depending on sets and games"
See entry 2025 for full details.

Djokovic 2-1 *Nadal
Easy for Djoko with his serve. A third ace racks up another comfortable game. The world number three has the edge but the match is still going with serve.

Djokovic* 1-1 Nadal
A sign of things to come with a cracking rally which ends with Djoko sending one long. 15-0. Let's hope there's plenty more of that. The commentators call the shirt purple! I've already had a tweet saying it was magenta! I said it was raspberry. Any other takers? Nadal trying to mix it up with a few looping forehands but a wild one makes it 15-30. Will this be another slow start for Nadal after losing the first set against Roddick on Monday? Another great rally and Djoko tries a delicate dropshot which just flops wide. Unlucky. Still a confident start from the Serb and a massive forehand has Nadal stretching and it's deuce. Is that Djoko sporting a goatee beard? Mmmmm A wayward back-hand gives Djoko his first break point but within a minute, we see Diego Maradona in the crowd and then an ace from the Spaniard and it's honours even. Plenty to enjoy here already.
* denotes NEXT to serve

Djokovic 1-0 *Nadal
Djoko wearing half-red and half-dark blue. A classic look. I like it. A 126mph cracker of a serve makes it 40-0 and it's soon game over. Smooth.
* denotes NEXT to serve

2025: The umpire calls time. A former barman is he? The players take one last swig of fluids and they're a few seconds from kicking off. If Djokovic wins tonight he will go through. Not so for Nadal if he wins - he'll have to wait. Seems like a great atmosphere in there. How's the atmosphere wherever you are? And where are you? Djoko to start by serving....LET'S GO.

Anonymous, via text 81111: "Greetings from Bermuda, its 4.15 this side, so yaah we are still at work, always love reading ur comments, I think Nadal will be on top of this group and he will play Murray in the semi and he will lose in two sets to Feds in the finals."
Welcome aboard this happy ship of live text. The two players are warming up to a dabble of Moby booming through the speakers. We're not far away now.

2019: Nadal is sporting a raspberry shirt. Combines well with the orange headband. Nadal's pre-match thoughts: "I feel good - no problems. I started nervy against Roddick but it's important to qualify. Novak is one of the best players in the world and he's a great competitor. I enjoy playing against him (sometimes) - it will be a tough match."

2016: Time for a coin toss. I think I'd call heads. What about you? It lands on heads 53% of the time doesn't it? And that's a fact. The Clash's London Calling is faded down. Djokovic calls HEADS and oh my lordy - it's thrown up and rolls off court - oh dear. Djokovic chases after it like a gazelle and it's a re-throw. What a bloomin' terrible throw. I've got to be honest - I've no idea who won that toss! Sorry folks. I can't lie. I was too busy enjoying watching Djokovic retrieving the coin. Sounds pretty noisy in there.

bbcsport_david on Twitter: "Celeb watch.. gracing the O2 tonight (drumroll pls) are Andrey Arshavin, Holly Valance & - yes, you guessed it again - Maradona"

2012: Djokovic strolls out with a big grin. His pre-match thoughts: "It's a big challenge - he's the best player in the world. I was a bit unlucky in the US Open but it's always a big struggle and you need to be on top of your game."

2011: Enough of my chat. This live text wants your chat and before the match begins. Usual rules apply. In fact, there are no rules, just give me your thoughts. Easy. Tweet me @bbcsport_mark, text me on 81111 (UK) or +44 7786200666 (worldwide) with TENNIS before your message, or join the banter on 606.

2009: By the way, I know you know that I know that I know that I'm at the BBC's TVC in London, for all gossip and latest news from the O2 itself then check out tweets from our man David Ornstein or the team from BBC Radio 5 live. Sky have got the TV action, live text commentary is HERE or why not tune into BBC Radio 5 live sports extra.

2006: Some stats for you. Nadal leads the head-to-head 15-7 with the Spaniard winning their only other encounter this year in the US Open final in September. But Djokovic leads their head-to-head on hard courts 7-4 which includes a win at the O2 last year in the final round-robin match. Nadal did not even win a set at the 2009 World Tour Finals and he said last week that he had been suffering from "playing with no confidence". Fingers crossed, Nadal is over his knee problems and although he hadn't played a match for five weeks in the build-up to these Finals, he's been practising hard at the indoor court in his Majorcan home. And judging by his eventual victory over Roddick on Monday night , he appears to be in red-hot form. Reckon Djokovic can cause any Spanish heartache tonight?

2002: Following Berdych's earlier 'shock' win against Andy Roddick (was it a shock?), the action from Group A continues with the pair that opened up with victories in their first round-robin matches. Whoever wins tonight should see themselves in the semis but there is everything to play for, particularly if progression goes down to the head-to-head or most sets won. So how do you see this battle going? I'd like to run a long bendy copper pipe into all your beautiful heads and withdraw all your thoughts. Actually, how about using the following three options to make things easier? Tweet me @bbcsport_mark, text me on 81111 (UK) or +44 7786200666 (worldwide) with TENNIS before your message, or join the banter on 606. Do it.

1959: Ladies and gentlemen, boy and girls, cats, dogs and budgies, I bring you Rafa Nadal vs Novak Djokovic. They'll be on the court in about 10 moments. (That's about 10 minutes)Two hulking heavyweights. Two giants in the game. The world number one vs world number three. Headband vs no headband. A 24-year-old vs 23-year-old. This year's winner at the French Open, Wimbledon and US Open vs quarter-finalist in Australia and France, Wimbledon semi-finalist and US Open runner-up. Long flappy brunette vs short spiky brunette. Smiley steely Spaniard vs smiley yet brooding Serb. Have I missed anything?

1957: The doubles is just coming to a conclusion and then it's time for the singles.....

1953: If it's fireworks, two of the planet's finest tennis gladiators slugging it out in front of 17,000 screaming fans at the London O2 arena, along with a whole load of words - including yours - attempting to describe this fizzing, bubbling feast of sport, then guess what? You've come to exactly the right place.