Venus Williams knocked out by Petrova

An inspired Nadia Petrova today claimed the biggest scalp of this year's French Open after beating Venus Williams for the first time in her career.

Petrova had lost all four of her previous meetings with the world number two but showed tremendous skill and resolve to seal a 6-4 6-3 fourth-round victory on Philippe Chatrier Court.

The 19th seed, who struck an impressive 28 winners and saved six break points today, will now play fellow Russian Elena Dementieva for a place in what would be her third Roland Garros semi-final.

Petrova was the villain on Phillipe Chatrier yesterday when she completed an epic two-day 6-7 (2/7) 6-4 10-8 victory over French golden girl Aravane Rezai, saving three match points in the process.

If she was suffering any comedown from that today, the two-time semi-finalist showed little sign in the first set, which began after a brief spot of rain on Chatrier.

After surviving deuce in her opening service game, the Russian cranked up the power in game five to break thanks to some crushing winners.

Williams, who had not faced Petrova in a WTA Tour match since 2003, did have break-back points in games eight and 10 but Petrova refused to yield in sealing the set.

She looked to have handed the American a way back into the match when she finally surrendered he serve in game two of the second set.

But Williams slumped from a winning position in game three to break point, eventually going long with a forehand.

And the second seed lost a crucial seventh game when she netted on a second break point.

Petrova then made it five games out of six to break Williams once more and seal a memorable victory.