QUÉBEC CITY, Canada - Four more Sony Ericsson WTA Tour stars moved into the quarterfinals of the Bell Challenge on Thursday, including Canada's biggest star, Aleksandra Wozniak, the last player into the round of eight.

Wozniak, the No.3 seed at the International stop, eased through the first set but was made to work in the second set, edging Regina Kulikova, 62 75.

Wozniak, who was born in Montréal and lives in Blainville, both cities also in the province of Québec, has always done well at the Bell Challenge. She reached her first Tour quarterfinal here in 2006 and last year made to the semifinals. She is the second-highest seed this year, after No.1 seed Nadia Petrova. No.2 seed Sabine Lisicki withdrew injured before the tournament.

In other matches, No.4 seed Lucie Safarova beat another French-Canadian, Valérie Tétreault, 62 62; Lilia Osterloh won a battle of qualifiers against Amra Sadikovic, 63 26 62; and Bethanie Mattek-Sands, who made her first Tour final here last year and is a wildcard this year, beat Vania King, 63 63.

Petrova, No.5 seed Melinda Czink, No.8 seed Julia Goerges and unseeded Alla Kudryavtseva all won second round matches Wednesday. The quarters will all take place on Friday, with Petrova facing Czink, Wozniak taking on Kudryavtseva, Safarova taking on Mattek-Sands and Goerges playing Osterloh.