Samantha Stosur will fancy her chances when she meets Frenchwoman Virginie Razzano in the third round of the hotly-contested WTA hardcourt tournament in Toronto.
Razzano set up a clash with the Australian by beating the in-form Italian Flavia Penetta 6-3 6-1 at the $A2.41 million event where most of the world's top players are having their last hit out before the US Open.
Penetta beat Stosur in the Los Angeles tournament final earlier in the month.
But world No.17 Stosur has beaten Razzano, ranked No.18, in both of their previous meetings, the last a comprehensive 6-1 6-2 thrashing at the French Open in June.
Stosur advanced to the third round a day earlier.
Meanwhile world No.1 Diana Safina suffered another setback when beaten while Serena Williams, Maria Sharapova and Kim Clijsters all advanced to the third round.
France's Aravane Rezai rallied to oust Russia's Safina 3-6 6-2 6-4. Safina made 17 double faults and struggled after losing last Sunday's WTA final in Cincinnati to Serbia's Jelena Jankovic.
Safina joined the seeded scrapheap in Canada that also includes No.3 Venus Williams, bounced on Tuesday by Ukraine's Kateryna Bondarenko. Safina blamed her service struggles on a number of issues.
"Ball toss was a disaster," moaned the Russian. "I don't move my legs. I'm jumping backwards instead of jumping forwards. I'm kicking it too much instead of hitting it more. I drop my head. I don't hold the left arm.
"I know this all, and I'm still so stupid that I'm continuing to do it."
The upset sends Rezai into a matchup against Russia's Alisa Kleybanova, who defeated Slovakia's Dominika Cibulkova 6-1 4-6 7-6 (7-4).
Serena Williams ousted Kazakh qualifier Yaroslava Shvedova 6-3 6-2, scoring eight points in a row at one stage as she booked a third-round matchup against Ukraine's Alona Bondarenko, the sister of the player who ousted her sister.
Serena swatted a lunging forehand winner to win the penultimate game of the match, doing a split at the finish and pumping her fist with joy.
"I'm really flexible," Williams said. "I love doing the splits off the court... I never really expect to do it on the court. On the hardcourt sometimes you can slide, and before you know it you just do the splits."
Even if Wimbledon and Australian Open champion Williams wins this week, Safina will top next week's rankings.
Belgium's Kim Clijsters, in her second event back since a two-year break to start a family, eliminated ninth seed Victoria Azarenka of Belarus 7-5 4-6 6-1.
Clijsters will next face fifth seed Jankovic, who defeated Swiss Patty Schnyder 7-5 6-4.
Sharapova, making a shoulder injury comeback, struggled but advanced by ousting Germany's Sybille Bammer, 6-3 7-6 (7-5). Next for her is Russian seventh seed Vera Zvonareva, who beat Italian qualifier Roberta Vinci 6-3 6-3.
"I'm actually having a competition with myself to see how many errors and double-faults I can make and still win the match in two sets," Sharapova joked.
"The fact that I served that way and still won the match in two sets is certainly going to give me a lot of confidence when my arm is where it needs to be and when my serve gets to where it has to be."
China's Zheng Jie broke Denmark's Caroline Wozniacki seven times in a 7-5 6-3 triumph. She next plays Czech Lucie Safarova, who beat Serbian 11th seed Ana Ivanovic 3-6 7-5 6-3.