The third-ranked Zvonareva, who received a first-round bye, rebounded from a tough opening-round match to move into the quarterfinals. She will next face Sabine Lisicki of Germany, who was a 6-4, 6-3 winner over American teenager Coco Vandeweghe.
Second-seeded Andrea Petkovic of Germany reeled off 10 consecutive games to lead 6-2, 3-0 when her French opponent Virginie Razzano retired with a right shoulder injury.
Petkovic will be an odds-on favorite in her quarterfinal, against 18-year-old American Sloane Stephens, who advanced when Austria’s Tamira Paszek quit with an abdominal strain when facing set point at 5-3 down in the first set.
No. 3 Agnieszka Radwanska breezed past American Christina McHale 6-1, 6-0 and the Pole should face a more challenging task against quarterfinal opponent Daniela Hantuchova; the eighth-seeded Slovak struggled past China’s Zheng Jie 6-2, 4-6, 6-4.
There was a better result for another Chinese, as fourth-seeded Peng Shuai won a thriller against Italian No.15 seed Sara Errani 4-6, 6-2, 7-6 (7). Peng was down a break in the third set.
Peng will face former world No. 1 Ana Ivanovic in the quarterfinals. The fifth-seeded Serb was a comfortable 6-1, 6-2 winner over Alberta Brianti of Italy.
After a struggle in the second round Tuesday against American qualifier Jill Craybas, Zvonareva was pleased with her performance against Dushevina.
“I started off a little slow but then I picked it up and it was a little bit better, a little bit cleaner than the previous one,” Zvonareva said.
Lisicki used two early service breaks to jump out in front 5-1 in the first set before Vandeweghe rebounded. The 19-year-old, who grew up less than 15 kilometers (10 miles) from the site of the tournament, fought back to within 5-4. Vandeweghe staved off two set points before Lisicki finally took the first frame.
“I didn’t play my best tennis,” Lisicki said. “The important point was that I pulled it through.”
