Top-seeded Belgian Justin Henin defeated sixth seed Nadia Petrova, 7-6 (7/4), 6-3 to advance to the semifinals of the 1.34 million dollar Rogers Cup on Friday.
Chinese qualifier Yan Zi also advanced to the semifinals the US Open tune-up as ailing Wimbledon finalist Marion Bartoli retired while trailing in their quarterfinal clash.
The world's top-ranked player, Henin captured one of her 34 career titles here in 2003 before falling to the retired Kim Clijsters in the 2005 final.
Playing in her first tournament since a surprising collapse in the semifinals at Wimbledon, Henin has been sharp in her first three matches, including a 7-5, 6-2 victory over China's Peng Shuai.
Henin has now won 11 of her 13 career meetings with Petrova, including seven of eight on a hard court.
The two also squared off here in 2003, with the 2003 US Open champion recording a straight-sets victory in the third round.
Petrova, who dropped just five games in dumping No. 10 Patty Schnyder on Thursday, last beat Henin in 2006 in the final of the claycourt Berlin Open.
In the semifinals, Henin will face Yan, was leading the seventh-seeded Frenchwoman 6-2, 3-0 when Bartoli decided she couldn't continue.
The 22-year-old from China was coming off a 6-3, 5-7, 7-6 (7/5) victory over Greece's Eleni Daniilidou on Thursday. She also upset No. 4 Ana Ivanovic in the second round.
On the other side of the draw, second seed Jelena Jankovic moved into the semifinals by defeating Virginie Razzano of France, 7-5, 6-2.
The Serbian, who posted a 6-2, 6-3 victory over No. 13 Sybille Bammer on Thursday, is looking for her fifth title of the year.
Jankovic said the blustery winds made playing difficult.
"We were, you know, both struggling a little bit because with this kind of windy conditions, the balls are not going quite where you want them to go. And especially in the serve, when you toss the ball, you have a little bit of difficulties," she said.
"My main focus was on the movement, to really move my feet and try to get behind the ball the best as possible, and really be focused out there. Watch the ball carefully because it's moving everywhere, so you really have to be focused. And you cannot let your concentration go down."
Jankovic had battled a stomach ailment on Thursday, but said she was feeling better.
"I took some medicine before I went on court, just for precaution, I didn't want to have the same like yesterday," she said. "It's not the best thing, but I felt fine during my match."
Jankovic will meet No. 12 Tatiana Golovin, who upset third seed Svetlana Kuznetsova of Russia, 2-6, 7-5, 6-1.
It was the second win for the Frenchwoman in three career meetings with Kuznetsova.