"Here we go again," Federer said of the prospect of facing Djokovic. "He's obviously looking for the big break here, so it's going to be a tough one."

The victory over Federer at French Open was Soderling's second victory in a row on the clay over a number 1 seed. In the fourth round at Roland Garros in 2009, Soderling knocked off Spanish sensation Rafael Nadal.

Prior to the French Open, Federer had bested Soderling 28 out of 30 sets. So it proved after Wednesday's clash that Soderling's luck just lies on the clay.

Federer also defeated Soderling in the quarterfinals of last year's U.S. Open in four sets 6-0, 6-3, 6-7 (6), 7-6 (6), before losing to Argentinean Juan Martin del Potro in the finals.

Third-seeded Novak Djokovic beat number 17 seed Gael Monfils 7-6 (7-2), 6-1, 6-2 in an earlier match.

The former runner-up here handled 17th-seeded Frenchman Gael Monfils by playing more aggressive to clinch 40 points from 59 trips to the net.

The tough first set went to Djokovic when Monfils played a rather poor tiebreak, and the second set was a throw-away one for the Frenchman, as the 2008 Australian Open champion Djokovic simply dominated the stanza.

In the third set, Monfils had a chance to break Djokovic to pull within 3-4 and then serve to tie things up, but the Serb managed a key hold to go up 5-2 and then broke his French counterpart to reach the semifinals.

Djokovic moved on in 2 hours, 28 minutes, as he broke Monfils no less than seven times en route to victory. The Serb tallied 13 more unforced errors (50-37), but he also connected for 21 more winners (38-17).

In the women's singles draw, top seed Caroline Wozniacki overcame unseeded Dominika Cibulkova in a dominant way, advancing to the semifinals also under windy conditions.'

The Dane, last year's runner-up, upended Cibukova of Slovakia 6-2, 7-5, setting up the semifinal matchup with Vera Zvonareva after the Russian beat Estonia's Kaia Kanepi 6-3 7-5 in another quarters.