Maria Sharapova beat fellow-Russian Vera Zvonareva 6-2, 7-6 (3) on Thursday to join Serena Williams in the quarterfinals of the Rogers Cup.
After waiting out a storm that suspended play for an hour, Sharapova eliminated the No 7 seed to advance past the third round of the Canadian tournament for the first time.
Zvonareva won four straight games in the second set before Sharapova recovered to force the tiebreaker, which she won easily. Williams had a much easier time, beating Ukraine's Alona Bondarenko 6-1, 6-4, two days after sister Venus Williams fell to Kateryna Bondarenko.
Serena Williams will next face Lucie Safarova of the Czech Republic. The second-ranked Williams is the highest-seeded player left in the tournament after No 1 Dinara Safina lost on Wednesday. Williams was disappointed with her performance, saying it wasn't as strong as her opening win against Yaroslava Shvedova the day before.
"I thought that if I could keep up that form, I'm on my way into glory and today I didn't play as well so hopefully I can get it back," Williams said.
The second-ranked Williams said she was focused on winning the Rogers Cup for the first time since 2001, and knew she will have to keep her cool.
"I get really emotional on the court," she said. "Sometimes I'm really into the game too much, and I've just got to (remain calm). I can't help myself when I do that, I think it's just something natural and hopefully it helps me. I think towards the end I was able to relax and just calm down and then just try to stay positive more than anything."
Bondarenko's sister Kateryna knocked out Venus Williams on Tuesday, but also lost her third-round match on Thursday. Kateryna Bondarenko, a qualifier, was beaten 7-5, 6-3 by 14th-seeded Agnieszka Radwanska of Poland, who advanced to her ninth quarterfinal of the year. Only three others have achieved more quarterfinals.
Williams will next face Czech qualifier Lucie Safarova, who beat China's Zheng Jie 7-6 (3), 6-4. Williams is the highest-seeded player left in the tournament after No. 1 Dinara Safina lost on Wednesday.
Earlier, fourth-seeded Elena Dementieva rallied past Shahar Peer of Israel 6-1, 1-6, 6-4. Dementieva will face Samantha Stosur of Australia, who swept Virginie Razzano of France 6-3, 6-1. Aravane Rezai of France couldn't repeat after her upset of Safina, falling 6-3, 6-4 to Alisa Kleybanova of Russia.