By Mark Elkington
MADRID (Reuters) - Seventh seed Jelena Jankovic failed to handle the blistering shots of outsider Aravane Rezai or the unseasonably cold temperature as she slumped out of the Madrid Open at the quarter-final stage on Friday.
Peer beat Li Na of China 6-4 3-6 6-4.
The combative Rezai was set on her way to a surprise victory when she won a marathon game on the Jankovic serve to put her 6-5 up against the Serb in the first set.
"It was the key game of the match," Rezai told reporters. "I knew I just had to keep on fighting."
With the roof open on court two the temperatures plunged as the evening drew in and Jankovic's shouts of frustration contrasted strongly with Rezai's yelps of encouragement.
Every time it looked like Rezai might be running out of steam she pulled out another powerful slug from the baseline and when she earned her first two match points her rival crumpled.
"It was like playing in the winter. The balls were heavy, there was no tennis, I had no rhythm and I didn't move well," Jankovic told reporters.
"Sometimes I don't think she (Rezai) knows where she's hitting the ball. She just goes for broke on every shot and it's difficult to read," Jankovic said.
"I just need to get my energy levels back and to feel fresh again," she said.
Venus Williams has pretty much seen it all and done it all on court so when Australia's Stosur tried a new tactic against her in their quarter-final, it failed to ruffle the American.
Stosur, who has never taken a set off Venus, gamely tried to overpower her opponent until her spirit was broken when she lost her serve to go 4-3 down in the second set.
Venus sensed her chance against the world number eight, and with her grunts echoing around the half-empty arena she blasted her way through the next two games, dropping only one point.
"I didn't think this was like a clay-court match, there were no rallies. It was just serve and hit hard. It was interesting," Venus told reporters.
"She's never beaten me before. She tried something new against me, but when people do that it just makes me stronger."
Venus has started the year well and is set to move up to number two in the tour rankings next week, behind her sister Serena, for the first time since May 2003.
The siblings are close to taking the number one slot in the doubles rankings as well.
"I like doing my job, my career, my life, my dog. I'm healthy and I've learned a lot," Venus said with a smile from ear to ear, as she tried to explain her run of form.
"If we can get the doubles number one it would be great. I don't think we ever thought we could do that."
(Editing by Alison Wildey and Ken Ferris)