An earlier than expected end to the afternoon session after Wawrinka's explosive display against Berdych. The Swiss won 95% of points on his first serve and 67% of points in total. Berdych, who did not earn a single break point, will hope he can recover from such a humiliating defeat by Wednesday. We'll be back for more live text commentary this evening when Marin Cilic takes on Novak Djokovic. Bye for now.
Post update
A crumb of comfort for Berdych - he usually wins his second round-robin match in this tournament. But Wawrinka and Novak Djokovic would be many people's favourites to progress to the knockout stages from this group. Djokovic will be in action this evening, against Marin Cilic, and there will be live text commentary on that, too.
Post update
Tim Henman
Former British number one on BBC Two
"I think Wawrinka, the way he's playing, has been difficult to predict all year. Twelve months ago he was fantastic here in London and he went on to win the Australian Open.
"But he has been up and down. Hopefully this is the start of another peak for him."
Post update
Berdych is the seventh best player on the planet, but was mullered this afternoon by a player who was not in the best of form before this tournament. The Czech sighed as he left the arena. There isn't much more to do to or say, I suppose.
Post update
"For me, when I play against him it's always tough," says Wawrinka, without a smirk, after fifth consecutive victory over Berdych. "But I can always find a solution, I'm really happy with the way I handled the situation today."
On calling his Swiss Davis Cup team-mate Roger Federer 'The Boss' on Twitter, Wawrinka said: "'Yeah he's the boss on the court, in the team and in the tennis world. He's such a legend and it is an honour to play with him in the Davis Cup team."
Get involved #bbctennis
dawn morris: I hope Stan charged him for that lesson
Maxwell: It's just been one of them days for Tomas, feel pretty bad for him actually
"I was expected a real fierce contest. This was not what we expected. These two players were complete polar opposites in everything they were doing. Wawrinka completely ran away with the match."
Game, set and match
*Wawrinka 6-1 6-1 Berdych
In an ideal world, Berdych would make Wawrinka serve for the match, but this world is far from ideal, especially for Berdych this afternoon. The Czech gifts the Swiss two match points. Once again Wawrinka pounces on the Czech's serve, steps in from the baseline, and Berdych fails to negotiate the barrier. Game over in less than an hour. A walloping.
Post update
Wawrinka 6-1 5-1 Berdych*
It's difficult not to feel sorry for Berdych, who is about to find himself on the end of a thumping defeat. He shows some willing to fight as the game progresses from 30-0 to 30-30, but Wawrinka throws in an ace and then drags Berdych towards the tape, a place where the beanpole Czech does not feel at home, and the 29-year-old nets.
"For Berdych, it has been a performance devoid of any belief - a lot of doubt in what he's doing. But with Wawrinka at the other end, you can see he loves playing here at the O2, totally believes in his tactics and his shots.
"I just wonder if - we've heard that Berdych is looking for a super coach and he approached Ivan Lendl - how much of a blow to his ego it would be to approach his fellow countryman and get a negative response."
Get involved at #bbctennis
Lots of discussion about who will be Tomas Berdych's new coach. And you've been busy letting us know on Twitter via #bbctennis who you think could do a job with the big Czech.
Rory: "Tough one. Tommy Haas? All court, could make Berdych a threat on all surfaces. Or Lleyton Hewitt has a good shout if he hangs up his racket this year."
Daron: "How about the cat Miroslav Mecir for Berdych's new coach?"
David: "Sampras for Berdych. Untested as coach and not communicator, but could bring slams, confidence, self-control, killer finishing."
Phil: "Somebody like Annacone would be a good choice for Berdych. He needs to adopt an attacking game a la Cilic."
Tim Henman as a coach? The former British number one says: "It's not for me, I wouldn't like the travel."
Any other suggestions? #bbctennis
Getty ImagesCopyright: Getty Images
Wawrinka breaks
*Wawrinka 6-1 4-1 Berdych
"Come on, Tomas," shouts a lady in the crowd, which seems to do the trick as the Czech launches a howitzer out wide to level at 30-30. Wawrinka wayward on the next return, which allows Berdych to slip ahead to 40-30 but the 29-year-old is unable to put daylight between himself and his opponent. A flick of the wrist from Wawrinka and a forehand flies by Berdych.
Deuce. Break point. Deuce. Oh la la! A shuffle of the hips, a flick of the wrist, and Wawrinka counter-punches with a clean winning return. A second break point for Wawrinka and that's all he needs. There's surely no way back for Berdych from here.
Post update
Wawrinka 6-1 3-1 Berdych*
Wawrinka has won 23 of 26 points on his own serve and Berdych, no matter how hard he tries, is unable to pose any threat, rarely does he get his returns back in the court. In just 90 seconds, Wawrinka holds to love.
Wawrinka breaks
*Wawrinka 6-1 2-1 Berdych
Berdych, perhaps because he has to, attempts to vary play by coming to the net but Wawrinka continues to retrieve with ease, forcing Berdych to net a simple volley. Wawrinka 0-30 up and Berdych is in danger. Again. The Czech, though, not being steamrollered in this set as he drags himself to 30-30 - coming out on top of a baseline rally as Wawrinka goes long.
Berdych races to the net once more, misses a chance to kill off his opponent with a volley and botches an attempted overhead when backpedalling to fetch a Wawrinka lob. Deuce. Eke. Double fault. Break point Wawrinka. Break point saved! Wawrinka netting.
Second break point... second break point saved. A brilliantly constructed point from Wawrinka which ends with a volley and the Swiss soon has a third break point. What can Berdych do? Surrender. A grizzly "come on" from Wawrinka as he punches the air in celebration.
Post update
Wawrinka 6-1 1-1 Berdych*
Lovely from Wawrinka, just lovely. The Swiss wins three points without reply and concludes with a ruthless winner down the line. How can Berdych stop a man who has found his rhythm and form?
Post update
Tim Henman
Former British number one on BBC Two
"Berdych's just got to put that first set behind him. Sometimes the predicament with today's players is there's no plan B.
"He's got to stick with plan A - but just play it a lot better."
Post update
*Wawrinka 6-1 0-1 Berdych
Better from Berdych. Much better. The Czech puts the strain of the first set behind him and comfortably holds to love by stopping Wawrinka from dominating from the back.
Post update
Piers Newbery
BBC Sport at the O2 Arena in London
APCopyright: AP
"Berdych - imbarazzante!" A bit harsh from the Italian journalist behind me but Berdych has made a dreadful start.
"The crowd, not surprisingly down on Sunday's Murray-Federer double bill, tries to get behind the Czech in the hope of seeing a contest but the set races away in 24 minutes.
"I'm pretty sure the Italian word muttered behind me is unprintable."
Game and first set
Wawrinka 6-1 Berdych*
There's plenty you can do in 24 minutes; cook up a nice plate of beans on toast, boil an egg, or perhaps run at least 400m. It's not often, though, a player wins a first set against a fellow top-10 pro in 24 minutes. Clinical from Wawrinka.
Post update
Andrew Castle
BBC tennis commentator on BBC Two
"This a horror show so far, as far as Berdych is concerned."
Post update
*Wawrinka 5-1 Berdych
A double fault from Berdych to start the game (his 191st double fault of the season, if that is of any interest to you). But the Czech, down though not yet out, battles to 40-15, with Wawrinka somehow ballooning his forehand backwards - a stroke which could have been caught at slip.
Wawrinka drags the game to deuce, though, with the Swiss nicking two points thanks to a beautiful crosscourt forehand winner and an ugly forehand miss from Berdych. Wawrinka patiently returning every ball, knowing that Berdych will eventually fold which he does - a backhand drifting wide for break point. A shrug of the shoulders from Berdych's girlfriend, but her man comes up with an ace and eventually pulls through to win his first game of the set.
Post update
Wawrinka 5-0 Berdych*
Wawrinka opens with an ace and these are uncomfortable times for Berdych. The Czech unable to keep his returns on target - another backhand into the tramlines presents Wawrinka with a 40-15 advantage and the Swiss is overpowering Berdych. A crackerjack of a forehand forces the Czech to net and surrender. Wawrinka closing in on the first set within just 20 minutes.
Post update
Tim Henman
Former British number one on BBC Two
"There's two sides to the coin with Berdych. Could he have a little bit more dexterity or feel on his returns to get back into the rallies?
"But at 6'5'' as a coach you would want him to use his size, use his authority to dominate opponents.
"The challenge for Berdych today is whether he can serve consistently and set up the big shots to make Wawrinka do the running."
Wawrinka breaks
*Wawrinka 4-0 Berdych
There will be plenty of time for Wawrinka to enjoy London at his leisure if he continues dictate the match. The 29-year-old may even make it out of the 02 in time to catch the 16:00 boat leaving for Westminster. The Swiss collects three break points with ease, taking the pace off the Berdych boomers and returning every serve. A straightforward break. Berdych has won just four of 21 points so far.
Post update
Wawrinka 3-0 Berdych*
Wawrinka comfortable on his own serve, cooking up an ace as he races to a 40-0 lead. Berdych, looking heavy of foot, is unable to dominate from the baseline.
"It'll be like a heavyweight boxing match out here. They're both going to go at each other and I wouldn't expect long rallies. It'll be an out attack match."
Wawrinka breaks
*Wawrinka 2-0 Berdych
Stan Wawrinka knows how to get under the skin of Berdych, beating the big Czech in seven of their previous eight matches with one of those encounters at this tournament last year. Wawrinka sowing some early seeds of doubt, hanging on to Berdych's coattails at 30-30. The pair then wrestle to deuce before Wawrinka, returning with confidence, earns a break point. Berdych's feet aren't moving in unison, the overcooks a forehand and the Swiss breaks early.
Post update
Wawrinka 1-0 Berdych*
There are gremlins playing havoc with our live text, but I will carry on regardless and hope everything sorts itself out. Solid serving from Wawrinka. A Berdych forehand into the tramlines takes the score to 40-0 and the Swiss holds with little fuss. "Come on, Stan, let's go," says one gentleman in the crowd.
Post update
BBC SportCopyright: BBC Sport
Australian Open champion Stan Wawrinka has not been at his best these last few weeks, losing in the opening round in Tokyo, Shanghai and Basel and suffering a third-round defeat in Paris. But the 29-year-old reached the semi-finals at the O2 last year and, if he needs a pep talk, he should tell himself: "I'm only one of three Swiss players to qualify for the season-ending finale". The others? Roger Federer (13 times) and Jakob Hlasek (a semi-finalist in 1988).
Fifth time lucky for Berdych?
BBC SportCopyright: BBC Sport
Berdych may have lost all four of his opening matches in this tournament, but the 29-year-old has enjoyed another consistent year, reaching five finals and winning two ATP World Tour titles, in Rotterdam and Stockholm.
Post update
But that was yesterday. Stan Wawrinka and Tomas Berdych have walked through a cloud of mist, which will remind those with good memories of London during the Dickensian era. Will it be Wawrinka or Berdych playing the role of the Artful Dodger, stealing and nicking points and pick-pocketing their way to victory. (I have no idea where I'm going with this, so let's move on).
Get involved #bbctennis
Rory Zachilroy: Buzzing for the ATP World Tour Finals. Come on Berdych!
Matt Hollister: Annoying all my colleagues by insisting that the #ATPFinals are on the office TV!! I have to brighten up my Monday's somehow!!!
Stan travelling in style
Stan Wawrinka/InstagramCopyright: Stan Wawrinka/Instagram
Andy Murray says in today's BBC Sport column that he's chosen to stay in London for this year's Tour finals, travelling to the O2 via boat. Looks like Stan is opting to test his sea/river legs too before today's match - according to his Instagram account.
That November breeze will wake him up.
Andy Murray column
You've probably heard that British number one Andy Murray lost his opening round-robin match on Sunday to Kei Nishikori. He's written about his 6-4 6-4 defeat in his latest BBC column.
"I felt good in practice but sometimes it doesn't happen for you out on the match court, and after a 6-4 6-4 defeat, now I have to try and win my next two matches - and win them well," says Murray.
"Last year I didn't even make it to this tournament because I had had back surgery, and recovering from that, as well as changing coaches, have made 2014 a real test.
"It's certainly not been my best year, but considering what I've been through it's been fine."
Post update
Piers Newbery
BBC Sport at the O2 Arena in London
"Tomas Berdych will want to change things up when he steps into the theatrical darkness and aqua blue of the O2 Arena for the fifth year in succession.
"The big Czech has lost all four of his previous opening matches, including last year against Stan Wawrinka, and needs to hit the ground running this time with world number one Novak Djokovic lurking later in the week.
"The good news for Berdych is that he's won all four of his second matches in London - so a win today and he's home and dry, surely?"
Post update
Hello! If you're looking for live coverage of the first Group A match of the ATP World Tour Finals you've come to the right place because we have live text commentary and video for you. Who's playing? Stan Wawrinka and Tomas Berdych. I know what you're thinking, a 'Meh Monday' has turned into a 'Marvellous Monday'. Tennis can do that to a person.
Post update
Getty ImagesCopyright: Getty Images
Another group, another four of the world's finest players competing in the most splendid of showdowns by the north bank of the Thames. Today three Grand Slam champions will entertain us, as well as the best male Czech tennis player since Ivan Lendl. Ready? Nice. [Cue the Clash's London Calling].
Live Reporting
Aimee Lewis
All times stated are UK
Get involved
Getty ImagesCopyright: Getty Images 
APCopyright: AP 
BBC SportCopyright: BBC Sport 
BBC SportCopyright: BBC Sport 
Stan Wawrinka/InstagramCopyright: Stan Wawrinka/Instagram 
Getty ImagesCopyright: Getty Images
Latest PostPost update
An earlier than expected end to the afternoon session after Wawrinka's explosive display against Berdych. The Swiss won 95% of points on his first serve and 67% of points in total. Berdych, who did not earn a single break point, will hope he can recover from such a humiliating defeat by Wednesday. We'll be back for more live text commentary this evening when Marin Cilic takes on Novak Djokovic. Bye for now.
Post update
A crumb of comfort for Berdych - he usually wins his second round-robin match in this tournament. But Wawrinka and Novak Djokovic would be many people's favourites to progress to the knockout stages from this group. Djokovic will be in action this evening, against Marin Cilic, and there will be live text commentary on that, too.
Post update
Tim Henman
Former British number one on BBC Two
"I think Wawrinka, the way he's playing, has been difficult to predict all year. Twelve months ago he was fantastic here in London and he went on to win the Australian Open.
"But he has been up and down. Hopefully this is the start of another peak for him."
Post update
Berdych is the seventh best player on the planet, but was mullered this afternoon by a player who was not in the best of form before this tournament. The Czech sighed as he left the arena. There isn't much more to do to or say, I suppose.
Post update
"For me, when I play against him it's always tough," says Wawrinka, without a smirk, after fifth consecutive victory over Berdych. "But I can always find a solution, I'm really happy with the way I handled the situation today."
On calling his Swiss Davis Cup team-mate Roger Federer 'The Boss' on Twitter, Wawrinka said: "'Yeah he's the boss on the court, in the team and in the tennis world. He's such a legend and it is an honour to play with him in the Davis Cup team."
Get involved #bbctennis
dawn morris: I hope Stan charged him for that lesson
Maxwell: It's just been one of them days for Tomas, feel pretty bad for him actually
Post update
Colin Fleming
British doubles player on BBC Radio 5 live sports extra
"I was expected a real fierce contest. This was not what we expected. These two players were complete polar opposites in everything they were doing. Wawrinka completely ran away with the match."
Game, set and match
*Wawrinka 6-1 6-1 Berdych
In an ideal world, Berdych would make Wawrinka serve for the match, but this world is far from ideal, especially for Berdych this afternoon. The Czech gifts the Swiss two match points. Once again Wawrinka pounces on the Czech's serve, steps in from the baseline, and Berdych fails to negotiate the barrier. Game over in less than an hour. A walloping.
Post update
Wawrinka 6-1 5-1 Berdych*
It's difficult not to feel sorry for Berdych, who is about to find himself on the end of a thumping defeat. He shows some willing to fight as the game progresses from 30-0 to 30-30, but Wawrinka throws in an ace and then drags Berdych towards the tape, a place where the beanpole Czech does not feel at home, and the 29-year-old nets.
Post update
Colin Fleming
British doubles player on BBC Radio 5 live sports extra
"For Berdych, it has been a performance devoid of any belief - a lot of doubt in what he's doing. But with Wawrinka at the other end, you can see he loves playing here at the O2, totally believes in his tactics and his shots.
"I just wonder if - we've heard that Berdych is looking for a super coach and he approached Ivan Lendl - how much of a blow to his ego it would be to approach his fellow countryman and get a negative response."
Get involved at #bbctennis
Lots of discussion about who will be Tomas Berdych's new coach. And you've been busy letting us know on Twitter via #bbctennis who you think could do a job with the big Czech.
Rory: "Tough one. Tommy Haas? All court, could make Berdych a threat on all surfaces. Or Lleyton Hewitt has a good shout if he hangs up his racket this year."
Daron: "How about the cat Miroslav Mecir for Berdych's new coach?"
David: "Sampras for Berdych. Untested as coach and not communicator, but could bring slams, confidence, self-control, killer finishing."
Phil: "Somebody like Annacone would be a good choice for Berdych. He needs to adopt an attacking game a la Cilic."
Tim Henman as a coach? The former British number one says: "It's not for me, I wouldn't like the travel."
Any other suggestions? #bbctennis
Wawrinka breaks
*Wawrinka 6-1 4-1 Berdych
"Come on, Tomas," shouts a lady in the crowd, which seems to do the trick as the Czech launches a howitzer out wide to level at 30-30. Wawrinka wayward on the next return, which allows Berdych to slip ahead to 40-30 but the 29-year-old is unable to put daylight between himself and his opponent. A flick of the wrist from Wawrinka and a forehand flies by Berdych.
Deuce. Break point. Deuce. Oh la la! A shuffle of the hips, a flick of the wrist, and Wawrinka counter-punches with a clean winning return. A second break point for Wawrinka and that's all he needs. There's surely no way back for Berdych from here.
Post update
Wawrinka 6-1 3-1 Berdych*
Wawrinka has won 23 of 26 points on his own serve and Berdych, no matter how hard he tries, is unable to pose any threat, rarely does he get his returns back in the court. In just 90 seconds, Wawrinka holds to love.
Wawrinka breaks
*Wawrinka 6-1 2-1 Berdych
Berdych, perhaps because he has to, attempts to vary play by coming to the net but Wawrinka continues to retrieve with ease, forcing Berdych to net a simple volley. Wawrinka 0-30 up and Berdych is in danger. Again. The Czech, though, not being steamrollered in this set as he drags himself to 30-30 - coming out on top of a baseline rally as Wawrinka goes long.
Berdych races to the net once more, misses a chance to kill off his opponent with a volley and botches an attempted overhead when backpedalling to fetch a Wawrinka lob. Deuce. Eke. Double fault. Break point Wawrinka. Break point saved! Wawrinka netting.
Second break point... second break point saved. A brilliantly constructed point from Wawrinka which ends with a volley and the Swiss soon has a third break point. What can Berdych do? Surrender. A grizzly "come on" from Wawrinka as he punches the air in celebration.
Post update
Wawrinka 6-1 1-1 Berdych*
Lovely from Wawrinka, just lovely. The Swiss wins three points without reply and concludes with a ruthless winner down the line. How can Berdych stop a man who has found his rhythm and form?
Post update
Tim Henman
Former British number one on BBC Two
"Berdych's just got to put that first set behind him. Sometimes the predicament with today's players is there's no plan B.
"He's got to stick with plan A - but just play it a lot better."
Post update
*Wawrinka 6-1 0-1 Berdych
Better from Berdych. Much better. The Czech puts the strain of the first set behind him and comfortably holds to love by stopping Wawrinka from dominating from the back.
Post update
Piers Newbery
BBC Sport at the O2 Arena in London
"Berdych - imbarazzante!" A bit harsh from the Italian journalist behind me but Berdych has made a dreadful start.
"The crowd, not surprisingly down on Sunday's Murray-Federer double bill, tries to get behind the Czech in the hope of seeing a contest but the set races away in 24 minutes.
"I'm pretty sure the Italian word muttered behind me is unprintable."
Game and first set
Wawrinka 6-1 Berdych*
There's plenty you can do in 24 minutes; cook up a nice plate of beans on toast, boil an egg, or perhaps run at least 400m. It's not often, though, a player wins a first set against a fellow top-10 pro in 24 minutes. Clinical from Wawrinka.
Post update
Andrew Castle
BBC tennis commentator on BBC Two
"This a horror show so far, as far as Berdych is concerned."
Post update
*Wawrinka 5-1 Berdych
A double fault from Berdych to start the game (his 191st double fault of the season, if that is of any interest to you). But the Czech, down though not yet out, battles to 40-15, with Wawrinka somehow ballooning his forehand backwards - a stroke which could have been caught at slip.
Wawrinka drags the game to deuce, though, with the Swiss nicking two points thanks to a beautiful crosscourt forehand winner and an ugly forehand miss from Berdych. Wawrinka patiently returning every ball, knowing that Berdych will eventually fold which he does - a backhand drifting wide for break point. A shrug of the shoulders from Berdych's girlfriend, but her man comes up with an ace and eventually pulls through to win his first game of the set.
Post update
Wawrinka 5-0 Berdych*
Wawrinka opens with an ace and these are uncomfortable times for Berdych. The Czech unable to keep his returns on target - another backhand into the tramlines presents Wawrinka with a 40-15 advantage and the Swiss is overpowering Berdych. A crackerjack of a forehand forces the Czech to net and surrender. Wawrinka closing in on the first set within just 20 minutes.
Post update
Tim Henman
Former British number one on BBC Two
"There's two sides to the coin with Berdych. Could he have a little bit more dexterity or feel on his returns to get back into the rallies?
"But at 6'5'' as a coach you would want him to use his size, use his authority to dominate opponents.
"The challenge for Berdych today is whether he can serve consistently and set up the big shots to make Wawrinka do the running."
Wawrinka breaks
*Wawrinka 4-0 Berdych
There will be plenty of time for Wawrinka to enjoy London at his leisure if he continues dictate the match. The 29-year-old may even make it out of the 02 in time to catch the 16:00 boat leaving for Westminster. The Swiss collects three break points with ease, taking the pace off the Berdych boomers and returning every serve. A straightforward break. Berdych has won just four of 21 points so far.
Post update
Wawrinka 3-0 Berdych*
Wawrinka comfortable on his own serve, cooking up an ace as he races to a 40-0 lead. Berdych, looking heavy of foot, is unable to dominate from the baseline.
Post update
Colin Fleming
British doubles player on BBC Radio 5 live sports extra
"It'll be like a heavyweight boxing match out here. They're both going to go at each other and I wouldn't expect long rallies. It'll be an out attack match."
Wawrinka breaks
*Wawrinka 2-0 Berdych
Stan Wawrinka knows how to get under the skin of Berdych, beating the big Czech in seven of their previous eight matches with one of those encounters at this tournament last year. Wawrinka sowing some early seeds of doubt, hanging on to Berdych's coattails at 30-30. The pair then wrestle to deuce before Wawrinka, returning with confidence, earns a break point. Berdych's feet aren't moving in unison, the overcooks a forehand and the Swiss breaks early.
Post update
Wawrinka 1-0 Berdych*
There are gremlins playing havoc with our live text, but I will carry on regardless and hope everything sorts itself out. Solid serving from Wawrinka. A Berdych forehand into the tramlines takes the score to 40-0 and the Swiss holds with little fuss. "Come on, Stan, let's go," says one gentleman in the crowd.
Post update
Australian Open champion Stan Wawrinka has not been at his best these last few weeks, losing in the opening round in Tokyo, Shanghai and Basel and suffering a third-round defeat in Paris. But the 29-year-old reached the semi-finals at the O2 last year and, if he needs a pep talk, he should tell himself: "I'm only one of three Swiss players to qualify for the season-ending finale". The others? Roger Federer (13 times) and Jakob Hlasek (a semi-finalist in 1988).
Fifth time lucky for Berdych?
Berdych may have lost all four of his opening matches in this tournament, but the 29-year-old has enjoyed another consistent year, reaching five finals and winning two ATP World Tour titles, in Rotterdam and Stockholm.
Post update
But that was yesterday. Stan Wawrinka and Tomas Berdych have walked through a cloud of mist, which will remind those with good memories of London during the Dickensian era. Will it be Wawrinka or Berdych playing the role of the Artful Dodger, stealing and nicking points and pick-pocketing their way to victory. (I have no idea where I'm going with this, so let's move on).
Get involved #bbctennis
Rory Zachilroy: Buzzing for the ATP World Tour Finals. Come on Berdych!
Matt Hollister: Annoying all my colleagues by insisting that the #ATPFinals are on the office TV!! I have to brighten up my Monday's somehow!!!
Stan travelling in style
Andy Murray says in today's BBC Sport column that he's chosen to stay in London for this year's Tour finals, travelling to the O2 via boat. Looks like Stan is opting to test his sea/river legs too before today's match - according to his Instagram account.
That November breeze will wake him up.
Andy Murray column
You've probably heard that British number one Andy Murray lost his opening round-robin match on Sunday to Kei Nishikori. He's written about his 6-4 6-4 defeat in his latest BBC column.
"I felt good in practice but sometimes it doesn't happen for you out on the match court, and after a 6-4 6-4 defeat, now I have to try and win my next two matches - and win them well," says Murray.
"Last year I didn't even make it to this tournament because I had had back surgery, and recovering from that, as well as changing coaches, have made 2014 a real test.
"It's certainly not been my best year, but considering what I've been through it's been fine."
Post update
Piers Newbery
BBC Sport at the O2 Arena in London
"Tomas Berdych will want to change things up when he steps into the theatrical darkness and aqua blue of the O2 Arena for the fifth year in succession.
"The big Czech has lost all four of his previous opening matches, including last year against Stan Wawrinka, and needs to hit the ground running this time with world number one Novak Djokovic lurking later in the week.
"The good news for Berdych is that he's won all four of his second matches in London - so a win today and he's home and dry, surely?"
Post update
Hello! If you're looking for live coverage of the first Group A match of the ATP World Tour Finals you've come to the right place because we have live text commentary and video for you. Who's playing? Stan Wawrinka and Tomas Berdych. I know what you're thinking, a 'Meh Monday' has turned into a 'Marvellous Monday'. Tennis can do that to a person.
Post update
Another group, another four of the world's finest players competing in the most splendid of showdowns by the north bank of the Thames. Today three Grand Slam champions will entertain us, as well as the best male Czech tennis player since Ivan Lendl. Ready? Nice. [Cue the Clash's London Calling].