Top-seed Nadia Petrova breezed into the second round at the Bell Challenge on Tuesday after easing to a 6-1 6-2 victory over Russian compatriot qualifier Maria Mokh.

The 26-year-old former world number three, who won her eighth singles title at Cincinnati, will face Varvara Lepchenko in the next round after the American qualifier beat Rossana De Los Rios of Paraguay 6-1 6-3.

Top ranked Canadian Aleksandra Wozniak, the fifth seed, took her first step towards a potential second title in 2008 after recording a 6-4 6-3 win over Romania's Edina Gallovits.

Wozniak captured her first career crown at Stanford in July and will next face American qualifier Carly Gullickson, who beat Romania's Stephanie Dubois 7-6 (8/6) 6-1.

Seventh seed Olga Govortsova of Belarus avoided an upset bid after rallying for a 6-1 2-6 6-4 victory over American Vania King, while France's Nathalie Dechy downed Germany's Anna-Lena Groenefeld in two sets.

Fourth-seeded Tamarine Tanasugarn of Thailand was not as fortunate as she was upset by Frenchwoman Severine Bremond 6-2 7-6 (7/4), while fellow seeds Sofia Arvidsson and Sabine Lisicki also fell at the first hurdle.

Eighth-seeded Swede Arvidsson suffered a 6-3 6-2 defeat by Kazakhstan's Galina Voskoboeva, while ninth seeded German Lisicki lost in three sets to Hungary's Melinda Czink.

Finally, American lucky loser Angela Haynes beat Canada's Stephanie Dubois 6-3 4-6 6-2.