Nadia Petrova stays strong to stun Venus Williams as Justine Henin digs deep against Sharapova

The American, a finalist in 2002, could not derail Petrova's consistent game on a windswept Centre Court as the Russian reached the quarter-finals for the first time since 2005.

"I had a day where I want to hit the ball crosscourt and it went down the line," said Williams.

Petrova, who saved three match points in the previous round against local hope Aravane Rezai, made up for an early break in the second set and wrapped up the win after one hour and 30 minutes. She will next face fellow Russian Elena Dementieva, the fifth seed, for a place in the semi-finals.

It was her first victory over the American in five attempts, and after the drama of seeing off Rezai in a match spread over two days due to rain the Russian was delighted to have fought her way through.

"It's my most dramatic French Open," Petrova, who reached the last four in 2003 and 2005. "I'm very happy I came back strong on that Centre Court."

Elsewhere, Justine Henin admitted Maria Sharapova gave her no choice but to go for broke after fighting back to beat her old rival and reach the fourth round.

Henin recovered from the loss of her first set at Roland Garros for five years to extend her winning run to 24 matches courtesy of a 6-2, 3-6, 6-3 victory.

Four-time champion Henin looked in real danger of her first defeat in the tournament since 2004 when 12th seed Sharapova had three points for a double break in the deciding set after the contest resumed this afternoon at one set all.

But the Belgian 22nd seed hit back to win five of the next six games and survive an enthralling encounter lasting two hours and seven minutes, spread over two days on Philippe Chatrier Court.

Saturday night had seen Henin equal the French Open record of winning 40 consecutive sets before Sharapova stopped her breaking it by levelling the match. That was after an atrocious start to the contest from the Russian, who had surrendered her serve twice as Henin moved 4-0 ahead. It was a different story yesterday morning, with Sharapova picking up where she had left off the day before.

Henin added: "She started the set very well. She's a champion, so as soon as you give her the opportunities – if you play a little bit too short and you don't take the opportunities – she takes them."

Sharapova refused to be down on herself for letting her final-set lead slip but felt she should have done better in the next game, which saw her drop serve. "At 2-1, I was a little bit more tentative than I was in the first three games," she said. "From the beginning, I felt like I was the one that was more aggressive of the two of us, and that kind of changed a little bit and changed the momentum of the match."

Henin will now play seventh seed Samantha Stosur in round four today.

Fifth seed Dementieva swept aside Chanelle Scheepers, 6-1, 6-3, while third seed Caroline Wozniacki beat Flavia Pennetta (14) 7-6 (7/5), 6-7, (4/7) 6-2.

The last eight sees the Pole play Francesca Schiavone (17), who beat Svetlana Kuznetsova's conqueror, Maria Kirilenko (30), 6-4, 6-4.