2228: Thanks for all your comments. Before I say nighty night, here's a pointer towards Andy Muray's latest column and David Ornstein's fine words on the Soderling v Ferrer match. More of the same tomorrow. Night.

2223: So Group B is all getting rather tasty. I'm sure most of you know, but if not, the final group standings go down to the percentage of games won. So, if all players end up with the same amount of matches won, then the tables are reflected by the number of games won divided by the number of games lost x 100 to get the percentage. Make sense? Basically, Murray will be a little happier that Ferrer came back in that second set but he will just have to focus on his own game and do what he can against Ferrer on Thursday. All very interesting. If Federer beats Soderling, it will be made a little easier for Murray. Is that all clear?

2217: A quick round-up from the earlier doubles. Jurgen Melzer of Austria and Philipp Petzschner of Germany beat Lukas Dlouhy of the Czech Republic and Leander Paes of India 7-6 (9-7) 4-6 10-8. Mariusz Fyrstenberg and Marcin Matkowski of Poland defeated top-ranked Bob and Mike Bryan of the US 2-6 7-6 (7-4) 10-8 in the late Group A match.

2213: Matches tomorrow at the O2 has Berdych playing Roddick - both players looking for a first win. And in the evening, it looks to be a firecracker with Nadal facing Djokovic. I'll be here for those games. Will you? I certainly hope so. I'm just checking out the permutations for Murray and co in this group. Even victory for Murray against David Ferrer on Thursday will not necessarily be enough to see him through - particularly if Soderling beats Federer.

2209: A relieved Soderling strolls up to the microphone and says: "I have good memories from this tournament. I played well last year and I've enjoyed coming back. I'm very relieved. It was tough. I served very well but I have a few things I need to improve. Federer [his next opponent] is playing well but at least I have given myself a chance to qualify."

Soderling 7-5 7-5 Ferrer
Soderling's return hits the net and dribbles over - big groans from the crowd as it goes to 30-30. That's harsh at this stage of the match. Soderling looks bemused and he shrugs his beefy shoulders in disbelief as a net shot makes it 40-30 to Ferrer. More deucey time and a wild forehand hands Soderling a match point. And Ferrer smashes his racquet into the court as he blazes one long and wide. Soderling wins 7-5 7-5.

Soderling 7-5 6-5 *Ferrer
The momentum has definitely swung in favour of the Spaniard. Ferrer comes into the net and swashes the winner away and then a double-fault gives Ferrer a 30-15 lead. Even more interesting than when I last said interesting. How interesting is that? Ferrer is battling for everything. Soderling still looking strong but he looks a little rattled at how hard he's being made to work for his points. It's deuce time but Soderling holds on. Ferrer will be desperate to keep up his work-rate. He needs a top service game.

Soderling* 7-5 5-5 Ferrer
C'mon David. Just keep up those grunts - are you hearing me? The boy needs a grunting coach to keep him in the zone. The Swedish wobble is like jelly now. Three bad errors and Ferrer is 40-0 up and one shot away from levelling the second set. And an ace does exactly that. Great stuff. Soderling has plenty to think about.

Soderling 7-5 5-4 *Ferrer
Maybe Ferrer should be grunting on every shot. It works again on the first point and he shouts "come on". Is this the start of the comeback? Another "come on" as the score reaches 0-30. Interesting. A Swedish mini-wobble. Ferrer needs the wobble to get wobblier. Nothing wobbly about the next serve though as 139mph of Swedish service power takes it to 30-30. Ferrer finds the baseline after a monumental rally and rightly challenges the call when it's called out. Big cheers as replays show it landed in. The first bit of drama tonight. Ferrer fighting for his life and with Soderling playing into the net, Ferrer gets his first break point. The crowd are finally loving it. And he grabs it. Very very interesting. The O2 has officially woken from its slumbers. The set back on serve.

Soderling* 7-5 5-3 Ferrer
It's all very quiet at the O2. I think they're all hoping for a three-setter. Ferrer does his best to keep in this match by edging his service game after a nervy deuce. The game is his after an ace and the crowd give him a massive cheer. Well done David.

Soderling 7-5 5-2 *Ferrer
Ferrer is flying all across the court to try his best to retrieve the booming serves but it's all for nothing. Soderling booms down his ninth ace to lead 40-15. And another ace gives him the game. Ferrer's hopes in the World Tour Finals are fading fast.

Soderling* 7-5 4-2 Ferrer
The Spanish wobbles come back to haunt Ferrer. He finds the net again as Soderling finds the baseline and it's 30-40. A big big point. And despite some astonishing defence from Ferrer, Soderling stays strong at the net and swipes the ball away like he's dealing with an annoying fly. He gets the crucial break.

Soderling 7-5 3-2 *Ferrer
Soderling's serve having a few more problems getting past the scampering Spaniard. Another big scream from Ferrer but Soderling hangs on. Those are the sort of games he will need to nab if he's going to have a chance of getting back in this match.

Soderling* 7-5 2-2 Ferrer
Ferrer dispatches a cracker to lead 40-15. The Spaniard marches off and he's got the spring back in his step. He'll have a job on his hands now though as the umpire announces "new balls".

Soderling 7-5 2-1 *Ferrer
Ferrer has a sniff at 30-30 on Soders' serve. Soders smashes it down to leave Ferrer unable to return and even John Cleese appreciated that cheeky little rally. Soders keeps his nose in front. Time for a quick word from John Cleese: "I'm fascinated. I love being so close because you can feel the impact of the ball on the racquet. It's not like a circus in the USA - I like the fact the audience are watching it and clapping politely." And then Cleese rounds off the conversation by accusing Mark Petchey of being an Aussie. The ultimate insult! Only joking. I need to take it easy with the Ashes just around the corner. Any Aussies around tonight?

2125: Keep your opinions, tennis thoughts and Christmas wishes coming in. Tweet me @bbcsport_mark, text me on 81111 (UK) or +44 7786200666 (worldwide) with TENNIS before your message, or join the banter on 606.

Soderling* 7-5 1-1 Ferrer
That's more like it. Call me old fashioned but I do like those cute shots at the net. Ferrer comes forward and dinks one across the court to take it to 30-15. He'll be happy with that - hold on. The smile turns to a growl as Ferrer finds the net and then again to give Soders a break point. A whole feast of back-hand slice from both players as the game bobbles along to deuce but Ferrer nicks it. That was hard work though.

Soderling 7-5 1-0 *Ferrer
A good opener for Soderling to lead 40-15 but then a double-fault gets him muttering to himself. The crowd yet to really get into this match and I'm still looking for those fireworks. Ferrer ploughs one into the net after a gut-busting rally to hand Soders the game.

Soderling* 7-5 Ferrer
A huge forehand winner gets Soderling to 30-0 against the serve. The Swedish snout will be sniffing the first set and he comes up to the net to make it 15-40. What was I telling you? Ferrer survives the first one and the second with two sloppy ones from Soders. More sloppiness takes it to deuce after fluffing a third set point. But Soderling hangs in there and takes the first set with a cracking curving forehand landing just inside the corner of the court after 48 minutes. Furious Ferrer and Soderling should be a little happier. Remember - both these players need a win tonight.

Soderling 6-5 *Ferrer
Yet another easy service game for Soderling. Ferrer has to do it all over again to save the first set. I see a tie-break around the corner. However, I feel something in my waters and I have a hunch Soderling may pounce right now. Let's see.

Soderling* 5-5 Ferrer
No sign of pressure showing for Ferrer as he takes a 30-0 lead and then plays a delightful back-hand cross-court winner from the net. He looks mighty relieved as he blows out a Spanish gasp - one of those gasps where your lips reverberate. You know the one? No problems as he takes the game with the minimum of fuss. Where's your money going with this one? It's getting interesting.

Lionel Hutz on 606: "You have to admire Ferrer. He gets no cheap point AT ALL. He just fights and fights. I wonder if he suffers from Monday morning blues."

Soderling 5-4 *Ferrer
It's Soderling's brutal forehands up against Ferrer's more subtle defence right now. Honours slightly with the Swede, due mainly to his superior serve. But it's close. Ferrer serving to stay in the first set.

Soderling* 4-4 Ferrer
First celebrity spot of the night goes to John Cleese. Cue the "Fawlty" gags from the commentator. You can guess what they were. Soderling plays a couple of very loose ones and lets Ferrer off the hook. Another big serve and it's all level again.

Soderling 4-3 *Ferrer
For all the sweat released in that last game, that one was a short one. Very. Soderling waves his racquet around a few times and he takes his service game in a matter of seconds.

Soderling* 3-3 Ferrer
Booming forehands from the back continue to dominate with few ventures into the net, although Soders strolls up just after I've written that to swipe the ball away to make it 30-30. Signs of a serve wobble? Oh yes. Ferrer, now under pressure, is facing a break point but he battles back with a combination of great defence and a nicely-controlled smash at the net to get it back to deuce. Best point of the match so far for the Spaniard. Ferrer is grunting for his life in this game and a wild one lets Soders in. Pressure back on but a huge serve that plants a kiss on the back line saves him. Strangely the grunts stop after the second deuce and it works. For a bit. The grunts return and it's deuce again. I'm officially confused at Ferrer's grunting tactics. The baseline battles carry on and it's like a metronome following this ball. Ferrer can't find his first serve when he needs it most but he has Soderling running from side to side to get it back to another deuce. A very key game. Ferrer holds thanks to a serve that kicks right up at the lanky frame of Soderling.

Soderling 3-2 *Ferrer
Soderling's sweat glands starting to work overtime but they are clinging to a man who is serving some missiles. A third ace - 143mph - at the end ensures the Swede keeps the lead.

Soderling* 2-2 Ferrer
The longest rally of the night so far as Soderling's rangy arms have Ferrer struggling slightly. The Spaniard keeps at it and even has the cheek to finish off the game with an ace. No sign of any fireworks yet. I did promise them earlier. C'mon boys.

Anonymous, via text 81111: "Managed to get to the O2 earlier and watch the king at work. Disappointed with Murray's performance, but it was my first time seeing Federer on the court. What an afternoon treat."

Soderling 2-1 *Ferrer
Soderling fires down a second ace of the match to lead 40-15 and after wrong-footing the Spaniard, Soders cruises into the net and blows the ball away. Nice.

Soderling* 1-1 Ferrer
Ferrer's serve just doing enough but Soderling plays a sweet winner to get it back to 40-30. The man in orange sweeps up. Honours even after a very steady start.

bbcsport_david on Twitter: "Not exactly the most rapturous of welcomes.. perhaps the crowd don't like RobSod's bannana yellow number, or is it DavFer's Tango orange top?"

Soderling 1-0 *Ferrer
A crushing serve x 3 hands Soderling a 40-0 lead, he whacks one wide of the lines and then he swiftly wraps up the first game. Quick stuff.
* denotes NEXT to serve

2022: The day's second Group B about to start. Soderling to crank up his rather lengthy serving arm. Here we go folks. I can't quite see the battery pack attached to Soderling's bright yellow shirt. It's a shocker. We're off.

2020: Ok. There was plenty of fashion news to tell you about earlier - Federer's tangerine effort, Murray's switch between white and black shirts after only two games. And while Ferrer and Soderling are warming up, 'what the heck are they wearing tonight?' I hear you cry. Soderling sporting a fluorescent yellow shirt. Useful if you're riding a bike in the dark but not very easy on the eye. Ferrer in orange. The Spaniard gets my vote. Just. Plus he's got the headband which always gets my nod. Only drummers and tennis players should be allowed to wear headbands. Have I missed anybody?

Heather in Manchester, via text 81111: "I really hope the top four players get through to the semi finals, hopefully Murray and Nadal on Saturday night as that's when I'm going!"

2012: The boys get ready to enter the arena and a few words from David Ferrer: "It will be tough against Robin. I will fight a lot."

BBC 5 live tweeting from the O2: "Ferrer/Soderling top the bill in London to a huge crowd. Barely believable, but fantastic. Played a classic at W'don. Could be a cracker"

2008: Stat-attack. Ferrer and Soderling are looking for their first wins and defeat tonight could mean curtains for their participation at the O2 this year. Soderling leads the head-to-heads 8-4 but Ferrer will be buoyed after winning two of their last three matches in the past seven weeks.
Battle 1 on 8 October - Ferrer won in quarter-finals in Beijing.
Battle 2 on 14 October - Soderling won in Shanghai.
Battle 3 on 6 November - Ferrer won in Valencia semi-finals.
And their record in these finals has Soderling reaching last year's semi and Ferrer runner-up in 2007. So honours even I reckon. How do you see this one going? This match matters for both of them. And did you know that if you added two extra letters to David Ferrer's surname, you'd get Federer. Interesting huh?

2003: If you were with me this afternoon, you'll know I'm currently strutting my stuff in London at Television Centre. For all gossip and latest news from the O2 itself then check out the tweets from our man David Ornstein or the team from BBC Radio 5 live. Sky have got the TV action, the live text commentary is HERE or why not tune into BBC Radio 5 live sports extra. Or just do it all. You can also watch video highlights of Murray v Federer. What more could you possibly ask for on a chilly Tuesday night? There's also live Champions League football text commentary with Sam Lyon. I will obviously be utterly gutted if you trade the tennis racquet for football. Although I guess you have the power to choose. Or do both. I am merely a messenger and awaiting your chat.

2001: So all thoughts wanted, desired, demanded. I don't care what those thoughts are. Predictions, opinions on Murray, Federer, Nadal, or even sightings of celebrities at the O2 or anywhere else. I'll even take on board any musings on what you might be requesting from Santa. I have a phone hotline straight to the bearded legend I'll have you know. Tweet me @bbcsport_mark, text me on 81111 (UK) or +44 7786200666 (worldwide) with TENNIS before your message, or join the banter on 606. It's that easy, so no excuses. I can't do this on my own.

1958: While we wait for the world number four and seven to wiggle their stuff at the O2, why would you not read Andy Murray's latest BBC column as he reflects on his disappointing loss to Federer this afternoon? I'd be interested to get your thoughts on what went wrong for Murray and how he should approach his next group match against David Ferrer. Does even Rafa Nadal have the skills this week to stop the Federer juggernaut from rumbling towards those million ATP dollars?

1954: A dabble of men's doubles just playing to a finish in a third set tie-breaker so the men's singles is just a matter of minutes away. I'll let you put the kettle on. Just come back right. I shall be waiting.

1947: Evening. It's David Ferrer and Robin Soderling in action tonight. I've put in a call to the entertainments manager at the O2 and they've promised me a bag full of fireworks following this afternoon's damp squib between Roger Federer and Andy Murray. Or was it just a damp squid?