Another point won on the back of an excellent rally by Boulter to kick off this game and she then whips a fierce return to the back of the court to go 30-0 up.

Pliskova then sends a shot long before a double fault gets Pliskova off the mark and a forehand return into the net by Boulter makes it 40-30 but then Boulter wins the game as Pliskova sends her return long.

David Law
Commentator on BBC Radio 5 Live

Karolina Pliskova did a good job of calming herself down there.

She is a player that can bubble away under the surface and they were warned by the umpire not to damage the surface

Boulter kicks off this game with a delightful backhand slice that drops just over the net, giving Pliskova no chance.

Pliskova wisely challenges the call for out to avoid a double fault and then nails her serve on the replay with Boulter unable to return.

More good serving and winners follow and Pliskova holds.

Staying on serve now after that manic couple of games as Boulter holds, sealing the game with an impressive winner on the back of an excellent rally.

Image source, Getty Images

Diego Schwartzman breaks Liam Broady's serve for the first time in the match to level matters up at one set apiece.

Broady sends a difficult overhead smash long to give Schwartzman two set points. He wastes both, one long, one into the net, but earns another with a dominant point at deuce.

And now it's Broady's turn to go long. Oh, bad time to throw in his worst service game of the match.

David Law
Commentator on BBC Radio 5 Live

Points and games can go by in a flash when Pliskova gets her serve going.

Pliskova has hit six aces today but also five double faults but when her serve is on point, it is really difficult for Boulter to deal with, as is the case in this game as Pliskova holds.

Big fight shown by Boulter, but she can't stop Pliskova breaking back.

Pliskova gets herself into a position where she has a couple of break points but Boulter battles back to deuce.

However, a winner for Pliskova follows before Boulter swipes a backhand return into the net. That's the fourth successive break in this match.

Laura Robson
Former British number one on BBC Radio 5 Live

This is where Pliskova's game breaks down a bit. Her serve is still a serious weapon but the consistency just isn't there anymore. The doubt starts to creep in and it affects other areas of her game.

Jonathan Jurejko
BBC Sport at Wimbledon

Well, well, well. Few saw that coming judging by the 'ooohs' of surprise which met Pliskova's double fault to hand over a break to love.

A comfortable hold for Diego Schwartzman means Liam Broady is serving to stay in this second set.

An excellent response by Boulter!

Pliskova's service game has been on point but Boulter finds a way to return them this time and breaks back.

A couple of rare double faults in there for Pliskova.

Diego Schwartzman is not having a great time of it in England this summer.

He lost in the opening round at both Queen's and Eastbourne, and also had cash and valuables stolen from his hotel room while competing in the latter event.

Now the 12th seed is having to really fight to avoid going two sets down to world number 132 Liam Broady.

The Argentinian is throwing everything he has at Broady, who is coping with it admirably and holds serve after being taken to deuce.

Pliskova immediately breaks back, however, with Boulter unable to take a point on her serve. A disappointing game after doing so well to get the break.

We're back on serve.

Laura Robson
Former British number one on BBC Radio 5 Live

Katie's brother James seemed to sense the break there, he had his phone out ready to video. He must have a sixth sense because I didn't see the double fault coming there. Pliskova is just not as good as she was at maintaining the level.

Jonathan Jurejko
BBC Sport at Wimbledon

It really does seem a peculiar decision to have the roof shut.

There doesn't appear to have been a drop of rain outside.

In fact, the indoor stadium has just illuminated with sunshine.

Until that break out of nowhere, Karolina Pliskova wouldn't have been complaining.

Playing indoors on grass - with no wind to disturb her serve and allow her to fire down rockets - was suiting her to the ground.

The adrenaline has kicked in and Boulter gets the first break of this second set, rattling off some excellent returns. Once again she is in a great opportunity to take control of this set.

A really good game by Boulter, highlighted by an excellent sweeping forehand down the line for the opening point as she once again finds her strength in the rallies.

She challenges a call for out at 40-30 on her first serve and it is the right call as it is indeed in, just! A great hold.

Kim Clijsters
Four-time Grand Slam champion on BBC Radio 5 Live

It's important for Katie to forget the five games after she was 2-0 up in the first set. There isn't much that she could have done differently, it's just the way the ball is coming off the racquet of Pliskova.

Once again, Pliskova's serve is too strong for Boulter and she seals the second game of the second set with an ace.

Boulter did win a good point at 15-0 down, flicking the ball down the line after Pliskova had approached the net, but needs to find more ways to deal with her opponent's serve.