SINGAPORE - No.7 seed Karolina Pliskova made a statement to start her third campaign at the BNP Paribas WTA Finals Singapore presented by SC Global, as she defeated No.5 seed and defending champion Caroline Wozniacki in White Group play, 6-2, 6-4.

Defeated by Wozniacki in the semifinals of last year's event, which the Dane went on to win, Pliskova never lost serve in the second match of Sunday's White Group action. 

The Czech joined No.6 seed Elina Svitolina as winners on the first day of round robin play, after the Ukrainian beat Petra Kvitova in the opening match.

Read more: Svitolina swiftly stops Kvitova in Singapore opening match 

"It's always tough matches against Caroline," Pliskova said on-court after the match. "The last time we played was here, and I remember the first set was more than an hour, and I had set points.

"I believed I had a chance because we had a very good match here last year and I tried my best today."

The Czech former World No.1 won five straight games in a dominant opening set, but needed three match points to secure her first win of the week in Singapore, as Wozniacki saved two in the ninth game of the second set. 

Pliskova's patented serve came to her rescue over the course of one hour and 32 minutes, as she saved all 10 break points she faced in the match - including two in the final game of the match which would've seen the Dane draw level.

"I felt pretty good from the baseline today, so not only just my serve," she added. "I think the game was pretty solid from my side. I think she started a little bit nervous because it's always tough to defend a title.

"I was just happy with my performance today. I was really enjoying tonight."

It was an unsettled start for the World No.2 and Australian Open champion, who saw her first two break points chances pass by in Pliskova's opening service game.

Despite hitting more winners than Pliskova in the opening set, with 10 to the Czech's eight, nine unforced to Pliskova's six and an 0-for-4 stat line on break points set back the Dane's cause.

Pliskova saved two more break points in the sixth game of the match, and after serving out the opener, her momentum continued with a third break of the Dane's serve to start the second set.