What a beautiful one-handed backhand return from Wawrinka - however that only reduces the gap to 40-15.

He goes from the sublime to the less sublime in the next point with a long return.

In the words of the late great David Coleman: "1-1!"

Tim Henman
Former British number one on BBC Two

Nishikori did a very good job of taking his opportunities. If you said 'how do you make an impact on Nishikori?' you would say you have got to take advantage of his second serve. In that set Nishikori hit his second serve 10 times and won nine points. That's a great stat for him but a poor stat for Wawrinka. It must improve.

Well, Colin he looks to be moving fairly freely.

It's 40-0 before the crowd have had a chance to sip their artisan hot chocolate.

Nishikori makes it 15-40 with another good low return before Wawrinka regains his composure to hold.

Colin Fleming
British tennis player on BBC Radio 5 live sports extra

Image source, AP

Part of me wonders if there's more to the strapping Wawrinka has on his knee. Maybe he's patched himself together a bit to be here and is a bit short of practice. In most tournaments you get an easier match first up than Kei Nishikori and can play your way in, but not here.

Here's what could prove to be the decisive moment of this first set.

Andrew Castle
BBC Sport tennis commentator

That is absolutely superb. What a set of tennis from Kei Nishikori, who has certainly come to play. You can see his gameplan - but it is one thing having a gameplan and another executing it.

Piers Newbery
BBC Sport in London

Image source, Reuters

There might be a few more patches of empty blue seats visible than in previous years, but Federer's absence hasn't stopped Swiss fans making their annual autumnal trip to London.

Unfortunately for the many decked out in red and white, there's been nothing from Wawrinka so far to get the cowbells clanging. We've had not so much as a "Hop Suisse!!!"

Balletic. Nishikori jumps up and performs a delicate backhand smash. Darcey Bussell wants your digits Kei.

Nishikori closes out the set by coming to net and killing a Wawrinka return with a deft volley.

Colin Fleming
British tennis player on BBC Radio 5 live sports extra

Nishikori has not allowed Wawrinka to get into the match. He hit the ground running right from the start and has been the aggressor. He is hitting the ball much more cleanly and you can see a bit of doubt creeping into Wawrinka's game.

Tim Henman
Former British number one on BBC Two

Nishikori is doing all the right things, being aggressive and trying to get Stan moving. Stan hasn't found his rhythm.  

Andrew Castle
BBC Sport tennis commentator

Image source, BBC Sport

Horrible. A complete collapse on that second serve. The ball toss perhaps not in the right place. But the mind has wandered a little bit.

You know how this live text commentary (and Henman) was raving about Wawrinka's serve. Well he's having a bit of trouble with it. 

0-30 becomes 15-40. 

Nishikori is reading what the Swiss is throwing at him. Then Wawrinka obliges with handing his opponent another break with a double fault. Poor.

Maybe Stan's thinking about hitting the Regent Street shops before rush hour.

The 26-year-old Japanese player holds. 

You know what they say "you're at your most vulnerable after breaking". 

Do they actually say that?

Any other tennis cliches you can think of? #bbctennis

Tim Henman
Former British number one on BBC Two

Nishikori is flattening the ball out and getting more help from the court.

Players have said it is warm in this stadium and the ball is playing quicker and I feel when Nishikori gets the chance to step in and dictate with the groundstrokes he is getting more benefit from the court.    

Andrew Castle
BBC Sport tennis commentator

Nishikori with great patience and pinpoint off the forehand side down the line. He's striking the ball sweetly.

"Fear my serve and volley Nishikori," says Wawrinka. But he messes it up badly - it's 15-30. And then 30-40.

It's break point after great defensive play from Nishikori from the baseline. Wawrinka really should have put the ball away when he was at the net. Disappointing.

The Swiss saves the first, but Nishikori makes no mistake with the next chance with a brilliant forehand that stretches the 30-plus-year-old man a wee bit too far.

Broken.

Colin Fleming
British tennis player on BBC Radio 5 live sports extra

Nishikori likes to hug the touchline and take the ball early. That could be effective for him because Wawrinka likes to have time to wind up his big shots. It could be an interesting facet of this match.

Wawrinka looks to just give up after the longest rally of the match with a wild swipe of the ball on the backhand. Boredom I guess? It's 30-0. And then 40-15.

A brilliant Nishikori ace fired out wide lands on the line. Wawrinka half questions the decision and then realises it's not worth his trouble. It was definitely in by the way.

Tim Henman
Former British number one on BBC Two

Wawrinka's first serve is a proper weapon. Nishikori's isn't.

He's got the serve working. Wawrinka wins his service game to love. Nishikori will find it tough to break that.

What does Tim Henman think?