The first two quarterfinals took place on Tuesday, including Sara Errani against Agnieszka Radwanska.
After losing the first set, Radwanska looked headed for a comeback, going up 3-1 in the second set.
Radwanska was thwarted though, as Errani fought back and pushed the second set to a tie-breaker.
The No.5-seeded Errani eventually sent the No.4-seeded Radwanska out of the tournament, 64 76(6).
The other quarterfinal was taking place over on Lenglen - Svetlana Kuznetsova and Serena Williams.
Williams was in trouble - she lost the second set and faced a 2-0 hole in the third, point for 3-0.
But like she has done so many times before, the No.1-seeded Williams dug out of that deficit.
Williams and Kuznetsova met at the net after Williams scored a 61 36 63 victory against the Russian.
Wednesday saw the other two quarterfinals take place including Victoria Azarenka and Maria Kirilenko.
Kirilenko had her chances, serving for the first set at 6-5, but Azarenka was just too tough.
The No.3-seeded Azarenka ended up taking the set and rolling to a 76(3) 62 win over the No.12 seed.
And over on Chatrier, Maria Sharapova was trying to figure out the riddle that is Jelena Jankovic.
The No.18-seeded Jankovic stormed through the opening set at love against the No.2-seeded Sharapova.
But things got much tighter - and much slipperier - from there for Sharapova's fellow former No.1.
Sharapova rebounded from a 6-0 first set for the first time in her WTA career, prevailing, 06 64 63.