Wow! What a day that was in the woman's draw. It really brought it to life and you know what? Today could be even better. For all the efforts of Maria Sharapova's conqueror, Sabine Lisciki – what a girl! – it's the prospect of Serena Williams against Petra Kvitova that really catches my eye.
This is going to be a battle royal; one of Wimbledon's greats against the reigning champion. Do not for one single moment underestimate the desire of Serena, for all she has done on the court and for all that has happened to her off it, to win Wimbledon again. And again, for that matter. Man, that heart still beats strong.
We saw that yesterday, when she beat Yaroslava Shvedova 6-1, 2-6, 7-5. She did not play at her best, she had some luck – that winning lob for one – but she goddamn won and that's all that matters. Serena knows she has to improve areas. She admitted that afterwards.
"If this was my best then I'm in trouble," she said. Don't worry Serena, that wasn't your best – and you know that too. I said right here after her first-round win over Barbora Strycova that she would be sticking around deep into the second week and I'm sticking to my guns. Today, though, will be a big test.
Serena was the last person to beat Kvitova at Wimbledon, in the semis in 2010, and Kvitova has become a better player since – she wouldn't be the defending champion otherwise. Kvitova said yesterday that semi was a big lesson for her – she has done her homework real well.
The advantage for Serena is that Kvitova plays only one way – she comes right at you, pow, pow, pow. Being a leftie as well brings a different line of attack. But Serena has the experience to deal with that. What she must not do when Kvitova comes at her is retreat. Do not drop back, Serena.
So much of her game is about power too – this could be an almighty slug-fest – and what makes the difference to Serena is if she stands strong on the baseline. If she does that, and does not allow herself to slip back, and takes the ball early, then it will be tough for Kvitova.
To a degree, Serena's match yesterday out on a windy No 2 Court was a good warm-up for today. Shvedova is another of these big hitters who throws herself at the ball and has a swing. We don't always know where it's going to end up (nor does she) when she winds up one of those big hits – and that is very like Kvitova's approach to the game.
Shvedova did well to come back after a one-sided opening set when Serena reeled off those big serves in between hitting some equally big returns back at Shvedova's serve. That final set lasted nearly an hour and it says everything about how that desire is still there in Serena. Don't doubt it, guys. This is her home from home.
Kvitova had a tough match against Francesca Schiavone. It was difficult in those conditions – the wind, the damp – but she kept her mind in the right place when her game was not at its best and pulled herself through. Schiavone has the heart of a lion and ran her hard but today is going to be so, so different.
Williams will run down every ball – that's the way Richard Williams taught his girls to play. It's a Williams mantra: run hard, run for every ball. Kvitova is a chaser too. Williams has the best serve in the women's game but the key area of this match should be how she returns the leftie serve of Kvitova.
There were moments against Shvedova when the return was booming and if that happens this afternoon she will have another semi-final place in her sights.
Today's big match: Serena Williams v Petra Kvitova
HOW THEY MATCH UP
US Nationality Czech
30 Age 22
Palm Beach, US Residence Fulnek, Cz Rep
Right-handed Plays Left-handed
5ft 9in Height 6ft 0in
6 World ranking 4
41 Career titles 7
$36m Career prize-money $7.4m
62-9 Wimbledon record 17-3
Winner x4 Wimbledon best Winner 2011
2 Head-to-head 0
3-5 Odds 13-10
Bollettieri's prediction: Williams in three sets