STANFORD, Calif. -- Fifth-seeded Sorana Cirstea beat American Coco Vandeweghe 6-3, 6-3 on Wednesday in the second round of the Bank of the West Classic.
The 32nd-ranked Cirstea, Romania's second-ranked player, reached the semifinals last year. She'll meet unseeded Olga Govortsova in the quarterfinal. Govortsova upset second-seeded Samantha Stosur.
Vandeweghe, who reached the final last year, went through qualifying to gain a spot in the main draw.
No. 6 Varvara Lepchenko also advanced with a 6-4, 6-4 victory over Austria's Tamira Paszek.
The 40th-ranked Lepchenko reached her second quarterfinal of the season. The American will face the winner of late match between top-seeded Agnieszka Radwanska and Francesca Schiavone.