Kvitova lets rip with her first aggressive roar of the match, celebrating a huge inside out forehand winner to move from 30-30 to game point. But two successive backhand errors gift Safarova her first break point and she takes it with an awesome backhand down the line. A smile stretches across the face of Safarova's dad in the player's box as his daughter gives him a nod after breaking back.

Tracy Austin
Two-time Grand Slam champion on BBC TV

"One part of the game that Safarova is better than Kvitova is movement around the court and scrambling to get to balls.

"Safarova has had the advantage of a nice draw but you can only beat the players in front of you and she has done a good job of winning handily in her matches so far."

Relief across the face of Safarova as she comfortably holds serve to get herself on the board. The Czech heads to her chair with a bounce in her step.

Stephan Shemilt
BBC Sport at Wimbledon

"Scorcher of a day at SW19, barely a cloud in the blue, sunburn if you haven't got suncream. The latter stages tend to mean quieter grounds, and there's plenty more space around the outside courts, which are all doubles, juniors and veterans. Still, standing a few feet from the fledgings is an eye-opener. These boys hit it hard."

Ros Clarke:, external They keep talking about how young Bouchard is. By her age, Martina Hingis had won five Grand Slam titles.

Safarova takes Kvitova to deuce, but once again, the 2011 champion's power proves too much and forces her opponent into a couple of errors to concede he game.

Tracy Austin
Two-time Grand Slam champion on BBC TV

"This match-up reminds me of the Roger Federer v Stan Wawrinka game from yesterday where you have to forget about who is on the other side of the net."

Ouch. That's not the start Safarova would have hoped for. At 30-0 up, the 23rd seed crumbles under a barrage of solid returns from Kvitova allowing the 2011 champion to break.

Lucie Safarova to serve first. Let the semi-finals begin...

Lindsay Davenport
1999 Wimbledon champion on BBC TV

"Petra was almost a reluctant champion and she is more comfortable and settled now. She looks like she is in a good place emotionally and is playing some of her best tennis.

"Safarova has never beaten Kvitova but she moves well out there. She is very well liked and is very fit and was so close to beating Li Na in Australia. For her to have some success now would be great but I worry about how she will cope against Kvitova's power."

Martina Navratilova
Nine-time Wimbledon singles champion on BBC TV

"This might be the only time Lucie gets to this stage. It might be her one chance and she needs to seize it which does put pressure on her. Kvitova is the favourite but if she is off her game, Lucie can beat her."

The players receive a rapturous reception as they stride onto Centre Court under delicious blue skies. Kvitova and Safarova are friends, having played at the same tennis club when they were younger.

Image source, Roger Rasheede

Grigor Dimitrov's coach Roger Rasheed:, external J Mac came prepared 2 hit with GD but I had 2 bump Mac due 2 his lack of experience @Wimbledon, I'll hit thanks Mac.

Image source, Novak Djokovic

Number one seed Novak Djokovic , externalwho will face Grigor Dimitrov in the last four on Friday: Breakfast full of love prepared by brother Marko.

Image source, AP

Kvitova and Safarova have played each other five times before, with Kvitova coming out on top each time. But Safarova, appearing in her first Grand Slam semi-final, will take heart from pushing Kvitova all the way in Eastbourne earlier this month, losing a tie-break in the decider.

Martina Navratilova
Nine-time Wimbledon singles champion on BBC TV

"I think Petra is sometimes too fired up and needs to calm down. She may have won too much too early in her career but now she is settled and playing more consistently.

"Petra has the biggest weapons and if they are firing she has a big advantage and it will be hers to win or lose. She also plays well against her friends."

Kvitova v Safarova is the first all-lefty Grand Slam semi-final in 22 years. The last time that happened was also at Wimbledon in 1992 when Monica Seles beat Martina Navratilova in three sets. Seles went on to lose in the final to Steffi Graf.

We're live on BBC Two with eight streams available at the top this page, too.

The first semi-final between 23rd seed Lucie Safarova and 2011 champion Petra Kvitova gets under way at 13:00 BST on Centre Court.

At the same time, fifth seeds Leander Paes and Radek Stepanek take on third seeds Daniel Nestor and Nenad Zimonjic in the men's doubles quarter-finals on Court One.

And if you're after a chuckle, watch court jester Mansour Bahrami in action in the men's invitational doubles on court two via the Live Coverage tab at the top of the page.

Anne Keothavong
Former British number one on BBC TV

Anne Keothavong on Twitter:, external A very exciting day for women's tennis at Wimbledon. Hard to pick who will win, all 4 players playing great tennis.

Lindsay Davenport
1999 Wimbledon champion on BBC TV

"My first Wimbledon semi final was a nerve wracking occasion. There was a nice moment earlier when Lucie Safarova came out and had a look around to get a sense of the atmosphere because she won't have played in such a big match here before."