Amelie Mauresmo survived a shaky second set to defeat 14th-seeded Elena Bovina of Russia 6-2, 3-6, 6-2 and advance to the quarter-finals of the $1.3 million Montreal Cup tournament in Toronto on Thursday.
Second seed Mauresmo, the 2002 champion and highest ranked player in the tournament, was pushed hard but rebounded nicely after dropping the second set.
"It was a big battle," the Frenchwoman said. "In the second set, I missed a couple of chances to break her serve and I got frustrated."
Mauresmo advanced to a Friday meeting against Karolina Sprem of Croatia, after the 12th seed upset seventh-seeded Ai Sugiyama of Japan 6-3, 6-4.
Also advancing were third seeded Anastasia Myskina of Russia, who easily defeated 15th seeded Chanda Rubin of the United States 6-4, 6-0.
Jennifer Capriati of the United States, the fifth seed, defeated Mary Pierce of France 6-2, 6-4 much to the disappointment of the locals.
The Montreal-born Pierce was a fan favourite all week.
"She started playing better in the second set, playing like she had nothing to lose," said Capriati, who lost the 2002 final to Mauresmo. "I had to stay in there and stick it out."
Capriati next meets unseeded Russian Elena Likhovtseva who upset 11th seeded Francesca Schiavone of Italy 6-2, 6-3 to advance.
Wimbledon champion Maria Sharapova was eliminated in a tight night match by fellow Russian Vera Zvonareva.
The 10th-seeded Zvonareva advanced with a 4-6, 6-4, 6-4 victory over the sixth-seeded Sharapova, as the 17-year-old sensation could not maintain her momentum after winning the opening set.
In another match, 16-year-old Tatiana Golovin of France downed Gisela Dulko of Argentina 6-7, 6-3, 6-4.