These are the kinds of matches that separate the men from the boys, or at least the champions from the ones that aren’t.  Stan Wawrinka hadn’t had such a great year, but after his four set win over Andy Murray, he had to feel good about his chances against Sam Querrey.  Meanwhile, Querrey had beaten Nicolas Almagro in three easy sets, and he had to feel good about not seeing Andy Murray, despite beating Murray a few weeks ago in Los Angeles.

The draw had opened up for both men. And it turned out, both were eager to win it.  The two split the first two sets, and as the match headed towards its fifth hour, Querrey had to play catchup, holding to stay in the match, while Wawrinka played the lead man.  Up 5-4 in the fifth, Wawrinka sprinted back on the court, in high kick jog, meant to show Querrey that he was as fresh as Nadal.  Querrey, for his part, played along, getting up early to serve.

In the end, Querrey lacked enough oomph on his first serve, while Wawrinka took his chances by coming to net in a chip-n-charge reminiscent of classic Aussies, John McEnroe, and Martina Navratilova, and Querrey was unable to pull out the critical passes in the waning moments.

Final score: 7-6 (9), 6-7 (5), 7-5, 4-6, 6-4

Because of the five set marathon, the winner, Stan Wawrinka will have his hands full trying to recover fast enough to play his next opponent.  Wawrinka has long been with his childhood coach, a man who coached him since he was 8.  But recently, he changed coaches and hired Peter Lundgren who has coached Roger Federer and Marat Safin.  Perhaps this new coaching arrangement has already paid dividends.

Wawrinka will need every bit of good coaching he can get because he plays Mikhail Youzhny next.  Youzhny took out American John Isner in four sets.  He then faced Tommy Robredo today.  Robredo used to be much better, but he’s not played well in sometime.  His fellow countrymen, Verdasco, Ferrer, even Juan Carlos Ferrero and Nicolas Almagro, have had better recent results.  Robredo also got a bit lucky beating two Frenchmen that retired part way through the match.

Despite this, Robredo did try to make the most of it, and took a set off of Youzhny.  Youzhny’s results (though not recently) have been better in the last year or so.  He played well after the US Open, and had a pretty solid clay court season this year (as solid as one can have when Nadal wins most of those titles).

Final score: 7-5, 6-2, 4-6, 6-4

The other two fourth-round matches feature an all-Spaniard affair.  David Ferrer took the first two sets over Fernando Verdasco, but Verdasco has taken the third set.  Rafael Nadal is waiting for the conclusion of Clijsters and Stosur so he can take on Feliciano Lopez.  Nadal lost to Lopez at Queen’s but he didn’t seem 100% (since Queen’s is played just after the French).  In any case, Nadal should be strongly favored over Lopez to reach the quarterfinals.