Sania Mirza bowed out of the women's singles at the Cincinnati Open after losing to top seed Patty Schnyder of Switzerland on Friday night.

The ninth seeded Indian ace was beaten 6-7(7), 5-7 in the quarter-finals.

In other quarter-final action, fourth seed Katarina Srebotnik of Slovenia beat sixth seed Marion Bartoli of France 6-2, 6-1 while Vera Zvonareva of Russia proved too good for fifth seed Jelena Jankovic of Serbia and Montenegro, winning 6-1, 6-1.

Serena Williams plays Amy Fraizer in the last quarter-final.

Sania and her Polish partner Marta Domachowska are in the semifinals of the doubles event, having scored a hard fought 6-4, 5-7, 7-6 victory over the Chinese-Uzbek pair of Meng Yuan and Varvara Lepchenko.