PARIS — Venus Williams' celebrated corset went under wraps Sunday, and now it's out of the French Open.

Playing with a long-sleeve top over her black lace outfit on a chilly afternoon, Williams lost in the fourth round to Nadia Petrova, 6-4, 6-3.

Williams came into the tournament seeded No. 2 behind her sister Serena, but Petrova spoiled the possibility of a sibling showdown in the final.

"I'm obviously disappointed," Williams said. "I feel like I had a day where I wanted to hit the ball cross-court and it went down the line. It just wasn't a good day."

Petrova has been a nemesis for the Williams family lately — she beat Serena in the third round at Madrid less than three weeks ago.

Justine Henin rallied in a winner-take-all set that seemed like a final, outslugging Maria Sharapova 6-2, 3-6, 6-3. The two former No. 1s returned to center court following an overnight suspension of the third-round showdown after two sets.

In men's play, top-ranked Roger Federer reached the quarterfinals in his bid for a second successive title, beating Olympic doubles partner Stanislas Wawrinka 6-4, 7-6 (5), 6-2.

Federer will next play No. 5-seeded Robin Soderling in a rematch of last year's final. Soderling advanced by beating No. 10 Marin Cilic 6-4, 6-4, 6-2.

No. 11 Mikhail Youzhny earned his first berth in a Roland Garros quarterfinal when No. 8 Jo-Wilfried Tsonga retired with a leg injury trailing 6-2.

Joining Petrova in the women's quarterfinals were No. 3 Caroline Wozniacki, No. 5 Elena Dementieva and No. 17 Francesca Schiavone.

On a damp, windy afternoon, Petrova and Williams bundled up. Only the flounce of Williams' buzz-generating corset was visible, while Petrova wore long sleeves and tights under a frilly skirt.

The Russian controlled rallies with steady play from the baseline and finished strong, a problem for her in the past. Petrova swept the final four games and wobbled only once, shanking an overhead when leading love-30 in the final game.

She collected herself and won the final two points, closing out the match with an emphatic forehand winner.

"I don't think she did anything super special, but I think she just played a little bit more consistently," Williams said. "The conditions aren't that easy with the rain and the wind."

Williams converted only one of seven break-point chances. In the second set she lost serve three times after taking a 2-love lead.

Serena Williams wore her playing outfit while watching her sister's defeat from the stands. They later teamed up in a third-round doubles match, beating Andrea Hlavackova and Lucie Hradecka 6-1, 6-2.

Petrova, seeded 19th, is a two-time semifinalist, but she's into the quarterfinals for the first time since 2005. The victory was her first against Venus in their five meetings.

Williams came into the tournament with the best record this year on the women's tour, but tricky footing has always made clay her worst surface. In 14 French Open appearances, she reached the semifinals only once — in 2002, when she lost to her sister in the final. She has advanced beyond the fourth round just once in the past six years.

Henin and Sharapova played the seesaw final set after the match was suspended late Saturday because of darkness. The pivotal moment came when Henin fell behind 0-2, love-40, then overcame four break points to hold.

She soon led 4-2, broke to go ahead 5-3 and served out the victory.

"I kept my chances to win this tournament," said the four-time champion, playing at Roland Garros for the first time since 2007. "I will give my best and enjoy it. It was a really good test."

The victory extended Henin's winning streak at Roland Garros to 24 matches. It was the first meeting between the two rivals since Henin spent 20 months in retirement before mounting a career comeback this year.

Henin next plays No. 7 Sam Stosur.

Federer struggled with the wind at times and fell behind 4-2 in the second set, but the No. 20-seeded Wawrinka couldn't hold the lead and missed an easy volley at 5-all in the tiebreaker.

When Wawrinka lost the set he mangled his racket, and Federer quickly pulled away after that. The defending champion has won all 12 sets he's played so far.

"I'm happy with the way things are going," Federer said. "I'm serving well, I'm moving well. Everything is fine."

Wozniacki, enjoying her best run at Roland Garros, needed three hours to beat No. 14 Flavia Pennetta 7-6 (5), 6-7 (4), 6-2. No. 5 Elena Dementieva beat unseeded Chanelle Scheepers 6-1, 6-3. No. 17 Francesca Schiavone defeated No. 30 Maria Kirilenko 6-4, 6-4.