Vera Zvonareva worried about possible semi vs. No. 1 Caroline Wozniacki

Vera Zvonareva is in the midst of her career season after a 6-3, 7-5 victory over Kaia Kanepi today that put her into the semifinals of the U.S. Open. It's the farthest she's ever advanced in this tournament, and it comes on the heels of reaching the Wimbledon finals, where Zvonareva lost to Serena Williams, who is out of this tournament with a foot injury.

But making back-to-back Grand Slam finals might be a tall order for Zvonareva. If form holds in the last of the women's quarterfinals tonight and top seed Caroline Wozniacki gets past unseeded Dominika Cibulkova, well, that might not be a favorable matchup for Zvonareva. They are 2-2 head-to-head, but she just lost to Wozniacki in the finals of the WTA event in Montreal in mid-August. Zvonareva defeated Wozniacki earlier this year in a clay court event when an injury forced Wozniacki to retire.

"If it's Caroline, she's playing great tennis at the moment," Zvonareva said, referring to Wozniacki's streak of three wins in her past four events. "We've played a few times, and we've always had tough matches. I'm expecting a very tough one in the semifinal. You have to be patient against her. She's a tough player because she reads the game well…She's very mature for her age. I think a lot of people are underestimating her."

In Montreal, Zvonareva was at a disadvantage because rain delayed her semifinal against Victoria Azarenka. She finally played it on Monday morning and then had to play the final that night.

"I had to play Victoria in the morning, and they have absolutely different styles of game, Victoria and Caroline," Zvonareva said. "It was very difficult for me to change the mindset and switch to another match."

In her quarterfinal against Kanepi, Zvonareva definitely was the stronger player mentally in terms of how well she handled the windy conditions. Kanepi, who had 60 unforced errors, bounced her rackets off the court a couple times and displayed her annoyance. "It was blowing in every way," Kanepi said of the wind. "Today was tough. I just didn't find the rhythm and the control of the ball."

Zvonareva demanded her share of credit for the problems Kanepi had, saying, "I don't think she was making errors for no reasons. I think I was making it difficult for her. She had to go more for her shots. I was trying to guess where she was playing and reading her game. With those conditions, it looks like an easy shot, but with the wind going all the different directions it's not easy. You have to make the right choices, and I had to step up and do a little bit more with the ball."