Capable German Angelique Kerber upset top- seeded Maria Sharapova in Friday's quarterfinal action at the Open GDF Suez.

The ninth-seeded Kerber upended the Australian Open runner-up Sharapova 6-4, 6-4 at Stade Pierre de Coubertin. The 24-year-old German piled up five service breaks, while the former world No. 1 Sharapova settled for three.

Kerber was a surprise U.S. Open semifinalist in September.

The three-time major champion Sharapova lost to Belarusian Victoria Azarenka in the Aussie Open finale two weeks ago and was also last year's runner-up at Wimbledon.

Second-seeded French crowd favorite Marion Bartoli barely avoided an upset, as the former Wimbledon runner-up came from behind to outlast seventh-seeded Italian Roberta Vinci 4-6, 6-4, 7-6 (7-2) in 2 hours, 40 minutes.

The hard-hitting Bartoli is trying to become the first Frenchwoman to title here since former world No. 1 Amelie Mauresmo turned the trick in 2009.

Bartoli's semifinal opponent on Saturday will be Czech veteran Klara Zakopalova, who upset sixth-seeded German Julia Goerges 3-6, 7-5, 6-1. Kerber will face Belgian Yanina Wickmayer, who defeated Kerber's German compatriot Mona Barthel 6-4, 6-7(3-7), 6-3 in Friday's final match.

The winner of this $637,000 event will pocket $107,000.