SINGAPORE - Defending champion Caroline Wozniacki evened her record in round-robin play in the White Group at the BNP Paribas WTA Finals Singapore presented by SC Global on Tuesday, defeating Petra Kvitova, 7-5, 3-6, 6-2.

Both players lost their opening round matches in Singapore on Sunday, but the defending champion's nearly two-and-a-half hour victory improved her chances of qualifying for the knockout stage, while 2011 champion Kvitova drops to 0-2 in the group. 

The victory is Wozniacki's first against the two-time Wimbledon champion in four years, with her last also coming at the WTA Finals. 

"I played much better today and I think I returned well, served well and moved well," Wozniacki said on-court after the match. "Against Petra, you just have to stay on your game, so I tried to stay focused and get a lot of balls back. I just had the belief and fought until the end."

Wozniacki withstood 40 winners off the Czech's racquet over the course of two hours and 19 minutes, as Kvitova also totaled 40 unforced errors. 

"I know Petra's patterns, but it doesn't always help. You know, she plays so fast that sometimes you just don't have time," the Dane added in her post-match press conference. 

"I think it worked well for me today, and I just tried to make her feel uncomfortable and make her feel like she couldn't be in position all the time, and it worked well for me."

The Australian Open champion served at 70 percent from the line, hitting three aces and saving eight of the 13 break points she faced, while also hitting 19 winners to just 14 unforced errors. 

Trailing by a break in the second set, Wozniacki was treated for a left knee injury. Though she leveled the set with a break for 3-3, she lost the next three games to send the match to a decider.

She rebounded strongly in the final set, breaking twice and saving the lone break point she faced to earn the win.

"I think I played somewhat similarly the whole match through, and I think in the second set I didn't think I played bad. I missed a couple of opportunities on my serve at 3-All, and I think she played really well to close out that set," Wozniacki said.

"It's the patella which was hurting me. You know, I'm just gonna tape it up, and that's worked for me in the past. It worked for me today. I got the first break in the first game of third set, and then just tried to think that I needed to hold serve. That was really it."