It's the last match before the US Open - the final of the New Haven Open at Yale.
WTA Staff

NEW HAVEN, CT, USA - Maria Kirilenko kept her breakthrough season going at the New Haven Open at Yale on Friday afternoon, getting past Caroline Wozniacki for a chance to play for the title at the Premier-level tournament.

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The No.7-seeded Kirilenko, who had never beaten Wozniacki in five previous tries, played clean, aggressive tennis to stay on serve with Wozniacki until 5-all, then got the first break of the match to lead 6-5 and held at 15 in the next game to take the set, 7-5. That would be the end, however, as her No.3-seeded opponent was subsequently forced to retire due to a right knee injury.

"In the past I had the same problem; sometimes you're moving fine, but some steps it really hurts," Kirilenko said. "When I'd play a good angle today I saw she didn't run for it. She was for sure having problems - and I think she made the right decision to stop playing today and rest her knee before the US Open."

"I could feel it from the start, and it started to get a bit worse," Wozniacki said afterwards. "I decided to stop because if you don't feel 100%, you can't compete at 100%. I wasn't going to win this match anyway if I'm not 100% at a fit level."

Wozniacki had been 20-0 at the tournament. "It's definitely not the way I would have liked to finish here, having won four times. This event has meant a lot to me. It was a big tournament for me to win back in 2008, then coming back and defending it in 2009 was huge, because it was the first time I had to go and defend a title. Then to defend it again and again, all of a sudden you're in this elite group that has won the same tournament four times. There are a lot of players who never win a title, and a lot of players who never win four titles.

"What happened this year was unfortunate, but I just need to move on."

And her prospects for the US Open, where she was a finalist in 2009 and a semifinalist in 2010 and 2011? "I'm going to take the rest of the day and tomorrow off and see how it feels, get some treatment on it, ice, then I'll be ready for the Open," she said. "I'll just take it easy these two days."

At night, No.2 seed Petra Kvitova out-hit No.4 seed Sara Errani, 61 63.

"I served well tonight and tried to attack the return," Kvitova said in her post-match press conference. "I wanted to be the player who took the offensive and hit the winners, because if I just push it back, who knows how it would be."

"I tried everything, but she was playing incredible on the baseline, hitting so strong without many mistakes. It was difficult," Errani said. "Today was not the best for me, but it was a very good tournament for me, reaching the semifinals."

Kirilenko leads Kvitova in their head-to-head series, 3-2. Their fifth meeting came just a matter of weeks ago at the Olympics, where it was Kirilenko who prevailed in the quarterfinals in straight sets. Kvitova leads on hardcourts, 2-1.

"It's going to be a completely different match because at the Olympic Games it was so windy it was tough to play rallies," Kirilenko said. "You never know what will happen. Everything depends on how we're going to play tomorrow."

"I didn't feel very good during the match against Kirilenko in London," Kvitova commented. "But I have to forget the bad things and pick up the good things. This time I'll just try to play my game, like I did today and yesterday."