Last year's runner-up Samantha Stosur was knocked out in the French Open third round after a 6-4, 1-6, 6-3 defeat by Argentina's Gisela Dulko on Friday.
Australia's Stosur, the eighth seed, began terribly as Dulko dominated all areas of the match without having to put in an especially sparkling display.
Stosur looked to have regained control when she hit back in the second set but the unseeded Dulko broke to go up 4-2 in the third as her opponent racked up 35 unforced errors.
Meanwhile, champion Francesca Schiavone reached the fourth round after opponent Peng Shuai withdrew during the second set with health problems.
The Italian was leading 6-3, 1-2 when China's Peng decided to pull out having been twice checked over by a doctor on court.
She had strapping on her left thigh and a plaster on her right knee but also appeared to have trouble breathing despite taking the advantage in the second set.
Schiavone, whose grunts got louder with every point, had made a shaky start but used her power rather than finesse to take a grip of the contest below cloudy skies.
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