SINGAPORE — Karolina Pliskova and Elina Svitolina secured opening round-robin match wins at the WTA Finals on Sunday.
Pliskova, who now leads the tour with 48 wins this season, defeated defending champion Caroline Wozniacki of Denmark 6-2, 6-4 in the second match.
Pliskova saved all 10 break points she faced in the match, including two when serving for the match in the final game. The Czech closed out the match on a third match point with an ace.
Earlier, Elina Svitolina of Ukraine ended a seven-match losing streak against Petra Kvitova of the Czech Republic for a 6-3, 6-3 win.
The seventh-ranked Svitolina, making her second consecutive appearance in Singapore, only earned qualification to this year's tournament last week when Dutchwoman Kiki Bertens failed to reach the Moscow semifinals. Later, Bertens made the final eight when No. 1-ranked Simona Halep withdrew with a herniated disk in her back.
"It's very nice to be back in Singapore and I'm very, very happy with the match tonight," Svitolina told the crowd. "I had to stay focused and be strong mentally. I had to play quickly and keep moving my feet so I need a massage now.
"You have to play your best level because everybody is very strong playing here."
Svitolina, who now holds a 1-0 record in the White Group, had only beaten Kvitova once before in their first match at the 2014 Cincinnati tournament. Sunday's victory was Svitolina's first win against a top-10 opponent since May.
The Ukrainian player briefly left the post-match news conference but later returned.
"I'm just not feeling good," said Svitolina after returning. A WTA spokesperson said Svitolina indicated she was feeling light-headed with slight nausea.
The fifth-ranked Kvitova, who won the year-end title in 2011, never looked settled and struggled with her serve throughout the 1 hour, 29 minutes match. Her first serve percentage was only 55, which made the task of beating Svitolina near impossible.
She double-faulted seven times in the match, including on set point in the first for Svitolina. Six of Kvitova's seven double faults came in the first set.
"I think she really played very consistent," Kvitova said. "Overall, yeah, it wasn't the best start, but the good thing is that there is still a chance to play better and to improve, and maybe go somewhere forward."
The Czech surrendered her serve in the opening game of the match but managed to recoup the break in the next game. But she was broken twice more in the first set to fall behind.
Svitolina set up the second set win by breaking Kvitova's serve to go ahead 4-2.
Svitolina said her win was an answer to any suggestions she didn't deserve to play here, having qualified so late for the draw.
"Winning this match definitely gives me lots of confidence," Svitolina said. "This win ... I want to take as one to go forward, and for all those people and haters that were saying that I don't deserve to be here and I'm not good."
Kvitova, who came into Singapore with a tour-leading five titles this season, and Wozniacki now stand at 0-1 in the White Group standings.
Wozniacki came into the late match with a 6-3 career record over Pliskova, including their last meeting in the round-robin portion of last year's WTA Finals.
Wozniacki's best effort in the match was saving two match points on her serve in the ninth game of the second set.