Caroline Wozniacki, Roberta Vinci win opening matches in Sofia

Sofia: Caroline Wozniacki and Roberta Vinci had easy straight-set victories Tuesday in their first round-robin matches at the season-ending Tournament of Champions. The top-seeded Wozniacki defeated Hsieh Su-Wei of Taiwan 6-2, 6-2 in 60 minutes while it took Vinci five minutes longer to rout Slovakia's Daniela Hantuchova 6-1, 6-2. Wozniacki converted all five of her break points and only lost her serve once, in the second set.

"I always try to finish my matches in two sets and I am happy that this time it worked," said Wozniacki, who is coming off titles in Seoul and Moscow. "I will try to finish this season with a hat trick." The fourth-seeded Vinci dominated throughout, breaking five times. The two traded breaks to start the second set, but the Italian then jumped out to a 4-1 lead to take control.

Wozniacki will play Vinci on Wednesday, with the winner likely clinching a spot in Saturday's semifinals. The first two in each group advance. In the other group, Bulgaria's Tsvetana Pironkova came from behind to dispatch sixth-seeded Zheng Jie of China 2-6, 6-4, 7-6 (4). Pironkova took a 3-0 lead in the third set before being forced into a tiebreaker.

Caroline Wozniacki and Roberta Vinci had easy straight-set victories in their first round matches at Sofia.

Russian duo Nadia Petrova and Maria Kirilenko earned straight-set victories in their first group matches. The second-seeded Petrova defeated No. 6 Zheng Jie 6-3, 6-3, handing her Chinese opponent a second loss in two days which will likely leave her without a chance of reaching the semifinals.

In the other match in the group, the third-seeded Kirilenko beat Tsvetana Pironkova 6-1, 6-4. Pironkova broke for a 2-0 lead in the second set but Kirilenko then won the next four games to take firm control of the match. Petrova and Kirilenko will meet on Thursday.

The Tournament of Champions features the six highest-ranked players who have won a title during the season but did not qualify for the WTA Championships, along with two wild cards. It is the final event on the WTA calendar.

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