Mason, Ohio, Aug 18 : The semifinals of the Western & Southern Open will feature a rerun of the men's Olympic bronze medal match between Novak Djokovic and Juan Martin del Potro.
Djokovic and Del Potro advanced in straight sets on Friday to set up the rematch from London. Del Potro beat Djokovic on Wimbledon's grass to win the bronze, the first of four medals for Argentina.
They'll go at it again Saturday on the hard courts in suburban Cincinnati.
"He won that match," Djokovic said. "It happens. You lose, you win, but the most important thing is to try to move on and become even better and even stronger from those experiences. And try to win."
Venus Williams needed another grueling match -- her third three-setter of the tournament -- to get past reigning U.S. Open champ Samantha Stosur 6-2, 6-7 (2), 6-4.
Williams has been coping better with an immune system disorder that causes fatigue, and it has showed in her results this week. Her latest win lasted 2 hours, 33 minutes.
The American raised both arms and jumped -- kicking up her heels -- after the final point.
"For me and everything that's gone on in my life, it's a huge achievement and I want to take it further," said Williams, who is 8-1 in three-set matches this season.
While Williams deals with her condition, Del Potro has been nursing a sore left wrist that he'll have examined before the U.S. Open, which he won in 2009. He beat France's Jeremy Chardy 6-1, 6-3 on Friday.
The right-hander missed most of the 2010 season while recovering from surgery on his right wrist. The doctor who performed that surgery will look at the other one following the Cincinnati tournament.
"The good thing: I'm not getting worse, so I can play," he said. "But anyway, I want to wait (for) what the doctor says because I have experience on my other wrist."
After winning his bronze, Del Potro went to Toronto and got knocked out in the first round of the Rogers Cup. He's still trying to get his game back to a championship level. The rematch with Djokovic on a hard court provides a good measure.
"I'm still feeling a little difference between the top players and me," he said. "But I know I'm getting closer very slowly, so that's important. I'm working for that."
Djokovic reached a Masters semifinal for the second straight week by knocking off Marin Cilic 6-3, 6-2. He won the Rogers Cup in Toronto last Sunday.
The Serb was fresh on Friday, having spent only a half-hour on court the previous day. Russia's Nikolay Davydenko had to quit after losing the first set 6-0 on Thursday night because of a sore shoulder that interfered with his serve.
"It was my best match so far here in this tournament," Djokovic said. "Came in the right moment, really."
Top-ranked Roger Federer was scheduled for the night match.
Rain interfered with two singles matches Thursday night, forcing tournament organizers to juggle the schedule.
Sixth-seeded Caroline Wozniacki was down a set to Russia's Anastasia Pavlyuchenkova when the rains came. Pavlyuchenkova finished off a 6-4, 6-4 win Friday morning, then had eight hours to rest before playing a quarterfinal match against fourth-seeded Petra Kvitova.
No. 9 Li Na's match against Sweden's Johanna Larsson was postponed before they could take the court Thursday night. Li needed only 64 minutes to win 6-2, 6-2 on Friday morning, leaving her less than seven hours to get ready for her quarterfinal match against top-seeded Agnieszka Radwanska of Poland.
