Tennis top seed Wozniacki toppled

Caroline Wozniacki's bid for a second-straight WTA Canada crown ended abruptly on Wednesday as the world number one was upset in her opening match by unseeded Italian Roberta Vinci. Vinci defeated the top-seeded Dane 6-4, 7-5 to reach the third round. Wozniacki, playing her first tournament since Bastad in the first week of July, had enjoyed a first-round bye. After dropping the first set, Wozniacki mounted a challenge, taking a 5-1 lead in the second. But Vinci, ranked 22 in the world, battled back to finish off the victory. "This is the best victory in my life," said Vinci, 28. "I was 5-1 down but I knew that I can win the set because it was a lot of wind, so some mistakes. "I tried to stay focused and play aggressive. That's it, this is the key (to) why I won the set." Wozniacki, winner of a WTA-leading five titles this season, had trouble with her serve in the windy weather. The conditions contributed to her seven double faults. "It was very difficult at first with the wind," Wozniacki said. "Especially when you threw it up. It was going everywhere, so definitely that didn't make it easy. It was blowing in different directions, but it's the same for both players." She was particularly disappointed that she couldn't at least win the second set to give herself a chance in a third. "I would have liked to have won that one and especially after leading 5-1 in the second," Wozniacki said. "It's not fun to lose this, but there's nothing really I can do about it now, just practice, and try to do better." Her early exit leaves the tournament without its top two seeds after second-seeded Kim Clijsters retired from her match against China's Zheng Jie with a stomach muscle injury that casts doubts on the Belgian's upcoming US Open title defence. Wozniacki and Clijsters led a strong field that included all of the WTA's top 20 players here this week. But one of the players most in the spotlight isn't even in that group, as Serena Williams arrived unseeded in the wake of her 11-month injury layoff that ended in June. The former world number one, who stormed through her first-round match, defeated Germany's Julia Goerges 6-1, 7-6 (9/7) to set up a meeting with Zheng. French Open champion Li Na of China advanced on a walkover when compatriot Peng Shuai withdrew prior to their match with a left hip injury. Peng hurt her hip last week in San Diego. "It is sad for her," said Li, the sixth seed. "Always tough when you're playing same-country player. We train together, we know much (about each other). Always tough." Wimbledon champion Petra Kvitova reached the third round with a 7-6 (7/3), 6-3 victory over Spain's Anabel Medina Garrigues. The seventh-seeded Czech came back from 5-6 in the first set, firing two aces past Medina Garrigues to make it 40-15. The 33rd-ranked Spaniard then netted a ball to force the tiebreaker. Rain halted the match at 4-2 in the second set, but Kvitova came back and secured the victory. Eighth-seeded Francesca Schiavone of Italy also reached the third round with a 6-1, 6-3 victory over Ekaterina Makarova of Russia on Wednesday. Schiavone converted five of her nine break-point opportunities to win in just over an hour.