PATTAYA, Thailand -- Vera Zvonareva won her 12th straight match at the Pattaya Open by beating Thai qualifier Nungnadda Wannasuk 6-1, 7-5 Thursday in the second round.
The two-time defending champion won the first four games before Wannasuk held serve for the first time.
Zvonareva reeled off the next two games to take the opening set, and then took a 5-1 lead in the second before Wannasuk battled back to tie it at 5-5.
Zvonareva took a 6-5 lead and the 21-year-old Wannasuk double-faulted twice in the final game.
"When she started making her shots, I didn't play my game anymore," Zvonareva said. "I just pushed the ball back and let her play the way she wanted to play."
Zvonareva will play Peng Shuai of China in the quarterfinals on Friday.
"She's been fighting for every point," Hantuchova said. "A lot of young girls could take a lot from her. It's tough at that age to keep fit. I really do admire her."