There are some truly terrific matches being played this Super Monday, with every man and woman remaining in the singles draws scheduled to play. But this match, for me, is the stand-out pairing because it promises brilliant quality and a mesmerising battle, mentally as well as physically.
I also know both girls extremely well and have worked with both of them. And of course they have both won Wimbledon titles, with Serena winning three, and Maria, famously, winning aged 17 in 2004, beating Serena in the final. Add into the mix that Serena is the defending champion and that Maria looks back in business after a long time out of contention, and we have a potential humdinger on our hands.
It's clear that Serena is most people's favourite, for good reason, because she's the world No 1 and in great shape, she leads their head-to-head 5-2, and competes with a feistiness bordering on channeled rage when she needs it. But their sole meeting to date on grass was the 2004 final, and Maria won. And Maria is a tough, tough cookie with determination unmatched on the tour when she's physically healthy and in the zone. This is fire versus ice, and not as easy to call as many might assume.
Let's consider their technical merits. Serena's forehands are just a bit stronger and their backhands are both solid. Serena's basic volley has the slight edge over Maria's, and both girls are brutally great with the swing volley, a stroke pioneered and perfected at my academy. Serena's serve is a little bigger and stronger at the moment, and she also enjoys edges in movement and physical strength.
Mentally, both these girls are so strong – they can't be separated. If you corner Serena, then she can turn into a predatory monster, and I mean that in a positive sense. Since she was a little kid, Maria has been demanding of herself and steely in trying to meet those demands.
I recall her as a young girl waiting on court to practice, eager to get on with it, taking the stance: "Let's get this frickin' ball game started!"
I think Maria's chance today lies in starting fast and hard, attempting to win in straight sets because although she's in decent shape, I'm not sure she's necessarily fully back to her stamina peak. If this goes into three sets, then the pendulum swings Serena's way.
Serena is the player under most pressure, first because she's the favourite, and second because she lost at Wimbledon in her only grass meeting with Maria. So Serena is supposed to win, and Maria can therefore play with the freedom of having nothing to lose.
Both these girls have the ability to win, and it's going to be close. Forced to pick a winner, I think Serena has the edge, based mainly on her staying power and physical condition.
Today's big match: Serena Williams v Maria Sharapova
How they match up
American Nationality Russian
28 Age 23
Palm Beach Gdns Residence Bradenton, Fla
1995 Turned pro 2001
Right-handed Plays Right-handed
5ft 9in Height 6ft 2in
No 1 World ranking No 17
36 Career titles 22
$31.2m Career prize money $13.3m
W53 L7 Wimbledon record W28 L6
Winner (3) Wimbledon best Winner (2004)
5 Head-to-head 2
1-3 Odds 3-1
Bollettieri's prediction: Serena to edge it, perhaps
Coaching report: Andy Murray v Sam Querrey
Murray can topple giant Californian Querrey with sharpness of his returns
Andy Murray was hugely impressive, again, when beating Gilles Simon on Saturday on Centre Court and he won by playing to his strengths: good serving, superb movement, the best returns in the game, mixing it up, being a little bit more aggressive than instinct typically dictates.
Today he faces Sam Querrey, a 22-year-old 6ft 6in Californian whose major weapon is the most enormous serve. That's the match right there for me: how Murray deals with that serve, or not. I think Murray will be able to cope because his returns are second to none and if he can get an early read on it, Querrey doesn't have a lot else to switch to.
Querrey had a long old match against Xavier Malisse to make the fourth round, needing five sets to get through, and that's going to take a toll on a guy with a big frame who needs to be fresh to move well.
As we move into the second week of the tournament, the grass is turning to dirt and the bounces are more unpredictable, but none of that will worry Murray. If he plays anything like he's played so far, then he'll win, in three sets, four at most.
Famous Belgians are ready to serve up a treat
We're fortunate in having such a mouth-watering prospect as Justine Henin against her compatriot Kim Clijsters so early in the tournament, relatively, but that's a result of them both still playing themselves back into the tour after returning from retirement. Looking at the technical aspects of their games first, their forehands are very different, Henin hitting flat and Clijsters with spin. Henin's one-handed backhand was one of the most deadly and beautiful weapons in the game at her peak but for sheer power I'd say Clijsters two-handed backhand has the edge.
Henin looked fantastic in the opening set against Nadia Petrova in the third round to take her career Grand Slam record in third-round matches to 27-0. Clijsters is in the fourth round at Wimbledon for the sixth time after her own straight sets win. This pair are level on the head-to-head stats, with 12 wins each from 24 meetings. Henin leads on grass, 3-1, but lost both meetings in 2010, both in three sets. I think this will go three. It's a toss-up, perhaps edging Henin's way through desire for that Wimbledon title.
Hewitt the supreme battler can knock out Djokovic
This is going to be a tough match for Novak Djokovic and the longer it goes on, the more it favours Lleyton Hewitt, stayer supreme. Hewitt took down Gaël Monfils in the third round and, having had a good rest, will be ready to go again.
World Cup of tennis
I have been trying to predict matches in South Africa based on the strengths of nations in tennis, and by assessing national sporting personalities and traits through tennis players I've known and worked with. Then, I project that on to the soccer and see what happens. South America has not been a continent well represented in Grand Slam successes, with a few notable Argentinian and Brazilian exceptions, but we need to look in that direction for today's big match.
Brazil v Chile
Now if I could imagine a Chilean woman who'd stand a chance against seven-times Slam winner Maria Bueno of Brazil then we could try that, but there isn't one. Let's instead look to the men's game and pitch Gustavo Kuerten of Brazil against Fernando Gonzalez of Chile, and, critical to this exercise, have them play on grass.
Kuerten won three French Opens, but didn't get beyond the third round in Australia or the quarters of the other Slams. He was a baseliner who liked the slow slugging that the clay at Roland Garros allowed. His single-handed backhand was a weapon. Gonzalez is one of the few current players to have reached at least the quarters in each of the Slams, and he's got Olympic medals to boot.
Now this pair actually met three times, always on clay, and Kuerten led 2- 1. But as we're talking World Cup, let's pretend grass. Chile's power shocks Brazil's languid artistry. Chile win tonight.
Win a week at my academy
Want a week's tennis holiday at my academy in Florida? Included in the prize is five days' top-class tuition. The prize can be for an adult wanting to shape up your game, or for a child who wants to follow in the footsteps of the likes of Andre Agassi, Monica Seles and Maria Sharapova, among other players who went from being kids under my tuition to No 1 in the world.
All you have to do is email to tell me who will win today's big match. I want a specific score line, and as a tie-breaker, a one-sentence summary of the manner in which your pick will win. All winners go into a hat, with one overall winner picked from there. Email: firstname.lastname@example.org
Yesterday's winner was Neil Thomas.
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