She will now play seventh seed Chanelle Scheepers of South Africa for a place in the semis.
Marion Bartoli of Italy beat the American Vania King 6-1, 6-2 to reach the quarterfinals. She will face Ayumi Morita of Japan next.
Chanelle Scheepers (RSA) – Yaroslava Shvedova (KAZ) – 4-6, 6-3, 7-6 (5)
Ayumi Morita (JPN) – Eleni Daniilidou (GRE) – 6-2, 6-3