SOFIA, Bulgaria - Caroline Wozniacki and Roberta Vinci were ruthless in their first matches at the Qatar Airways Tournament Of Champions Sofia on Tuesday, both moving to 1-0 in their round robin group with quick wins.

The No.4-seeded Vinci was first to take the court, in fact the first winner of the week, carving out a 61 62 victory over No.7 seed Daniela Hantuchova.

"I was playing well - when I'm playing well it's difficult to play against me. I don't think she was comfortable with my game," Vinci said. "If I continue to play like this I think I have a good chance at making the semis or final this week."

Hantuchova echoed the assessment. "I never go onto the court not believing in myself - but today she played extremely well, not making any mistakes, especially in the first set," the Slovak said. "She totally outplayed me, and all of the credit to her for the way she played against me out there today."

At night, No.1 seed Wozniacki made quick work of No.5 seed Hsieh Su-Wei, beating the Taiwanese trailblazer in exactly 60 minutes, 62 62. It was a big difference from their last meeting in Beijing a few weeks ago, where Wozniacki trailed a set and 3-0 - and even faced points for a 4-0 deficit in that second set - before finding her range and grinding out a marathon 67(5) 76(3) 60 victory.

"I was just trying to do my best, and obviously you always want to win in two sets," Wozniacki said. "I'll just do my best in my next matches too."

Wozniacki's next match is coming up on Wednesday too, against none other than Vinci - and Vinci actually won their only previous meeting, in 2011.

"It's going to be tough - Roberta changes the rhythm up a lot," Wozniacki said. "I'll have to be prepared for that - it's going to be a tough one tomorrow."

Wozniacki isn't just looking to add to her career haul of 20 WTA titles this week, she's also looking to move back into the Top 10 - if she wins this title, or even if she reaches the final undefeated, she will move from No.11 to No.10 - she fell out of the Top 10 after falling in the first round of the US Open in August.

Wozniacki and Vinci are now up 1-0 in Group Serdika, while Hsieh and Hantuchova are 0-1. The group names - Serdika and Sredets - are two central districts of Sofia, and also names given to the city in ancient times.