Serena Williams, the warrior queen of SW19, blasts champion Petra Kvitova out

What do you get when you combine 120mph serves, velvet drop shots and skirts? A woman almost impossible to beat on grass. The outgoing champion Petra Kvitova was the latest to stand in the Serena Williams coconut shy and wither. She described her Centre Court experience yesterday as "big difficult". We knew what she meant.

The effort and will required to contest a Williams service game inevitably heaps pressure on one's own. Perhaps now that her title is gone, Kvitova will understand better what she had. Her year as Wimbledon champion has been a learning experience. She is the only member of the women's top-10 not to win a title this year, which suggests that she is still coming to terms with all that being a champion means. "I'm sorry to leave in the chorus line but I have something to build on," Kvitova said.

Williams is two victories from a fifth Wimbledon crown and 14 Grand Slams. There is nothing about the experience that is new to her. And at 30 years old, there is no obvious sign of a diminution of her athletic attributes. You have no trouble believing her when she says that she does not walk in fear when the mob closes in for that picture or autograph. My money would be on Williams were the melee ever to turn ugly. This is not to question her femininity, only to pay tribute to her impressive physicality and spirit. She is the embodiment of Wimbledon's warrior queen, a woman to follow into the fire.

Kvitova was smoked 6-3, 7-5. She left nothing on the court. Every ounce of her competitive fibre was deployed in this quarter-final. And on the odd occasion when Williams dropped the percentages, Kvitova climbed into the ball with a fearsome intensity. But in the second week of a major tournament, when her eye is in, her technique is sound and her focus sharp, Williams is just too good.

The baseline scramble with Kvitova dominating game point at 3-3 on serve in the second set was quintessential Williams; falling over, getting up, contriving a shot of sorts, sprinting to get her racket on the incoming missile. Williams lost the point and the game, but the effort expanded by Kvitova to win it cost her any chance of contesting the next. In the blink of an eye the ball was back in Kvitova's hand and so the cycle repeated.

Kvitova had to wait an hour before fashioning a break point. It co-incided with set point. Williams blasted her response to the affront. Deuce. Two points later it was 'game Ms Williams', the final point decided in part by a shot rifled straight at Kvitova. The Czech got a racket on it but served only to scoop the ball up for a Williams winner.

At least Kvitova had dragged herself into the fight. Too late, of course. Williams broke in the next game, the 11th of the second set, and fired three more aces at Kvitova to close out the match. She wasn't even out of breath. "I had nothing to lose. I am enjoying every minute of this, having the time of my life. My goal is to win two more matches in this tournament." Williams said.

"It wasn't about dethroning the champion but playing well. You can't play a defending champ without raising your game. You have to weed out the riff raff and get serious. I talked with my dad and Serena about it, and took to heart what everyone said." Williams will play Australian Open champion and second seed Victoria Azarenka, who ended Eastbourne champion Tamira Paszek's nine match-winning streak in straight sets, 6-3, 7-6.

Angelique Kerber triumphed over Sabine Lisicki in a thrilling German derby. After her victory over No 1 seed Maria Sharapova, Lisicki appeared hungover in the opening set and was required to save three match points in the second to stay in the tournament. Lisicki served for the match at 5-3 in the third but could not convert and on her fifth match point Kerber, playing for the first time on Centre Court, made it home 6-3, 6-7, 7-5.

Kerber will meet Agnieszka Radwanska, who eventually accounted for Maria Kirilenko 7-5, 4-6, 7-5 on Centre Court nine hours after the rain-affected match began on Court One.