Russian teen Anastasia Pavlyuchenkova sent third seed Vera Zvonareva crashing out of the French Open on Sunday to further throw the tournament wide open.
With the two top seeds, Caroline Wozniacki and Kim Clijsters already out, Zvonareva's departure after a 7-6 (7/4), 2-6, 6-2 loss means that fourth seed Victoria Azarenka of Belarus is the top-ranking player left in the draw.
For 19-year-old Pavlyuchenkova, the win represents a major breakthrough as it will be a first appearance in a Grand Slam quarter-final.
Her opponent will be either defending champion Francesca Schiavone of Italy or Jelena Jankovic of Serbia with a place in the semi-finals the prize for the winner.
Pavlyuchenkova, the youngest player left in the draw, got off to the perfect start with a break of serve and led 2-0 before her more seasoned compatriot ran off four games in a row.
Zvonareva served for the set at 5-3 but was broken as the 2006 world junior champion forced a tie-break.
The younger and taller of the two Russians took early control of that with some big-hitting groundstrokes from the baseline giving her a 3-0 lead and she held on to that advantage to pocket the first set in 57 minutes.
That was the cue for Zvonareva to enjoy her best spell of the match in which she won four games in a row to dominate the second set.
Another break of serve to Zvonareva in the third game of the decider could have deflated Pavlyuchenkova, but instead she rallied strongly to level and after winning a marathon fifth game, she raced away to pull off an impressive win.