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.

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.

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."

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.

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.

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."

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.

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.

Image source, 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).

Image source, 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.

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).

Rory Zachilroy:, external Buzzing for the ATP World Tour Finals. Come on Berdych!

Matt Hollister: , externalAnnoying all my colleagues by insisting that the #ATPFinals are on the office TV!! I have to brighten up my Monday's somehow!!!

Image source, 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.

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."

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?"

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.

Image source, 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].