By John O'Brien
SINGAPORE (Reuters) - Sloane Stephens maintained her unbeaten record at her first WTA Finals with a second successive victory on Wednesday, laying down the foundations of a three-set win over Kiki Bertens as the second set was slipping away.
Stephens eventually overcame the Dutchwoman 7-6(4) 2-6 6-3 to sit on the brink of a semi-finals berth after the 2017 U.S. Open champion used the seventh game of the second set to determine the tone for the decider.
"I was down 5-1 in the second. I was like, 'just play the next game like how you want to play in the third set and just try as hard as you can'," Stephens told reporters.
"...Then in the third set I was just telling myself the same thing. She played such good points... so I couldn't really get too down on myself.
"I think when I pushed through that and stayed positive, I was able to get a little bit of momentum. I was right there. When my coach came on the court, he's, like, 'You're right there. You've just gotta push a little bit more'.
Stephens felt playing a versatile player such as Bertens gave her plenty of problems to solve on her way to winning an encounter in some ways akin to a chess match.
"She was doing a lot of different things... normally you play a lot of players who are just very straightforward and they only do one thing, like they just hit really hard or hit a lot of spin," the 25-year-old world number six added.
"I think someone who mixes it up a lot, you have to mentally stay in the match... I think we both really did that well today, and obviously someone has to lose but I thought we played a really good match."
Stephens, who beat Naomi Osaka in her first match, will top the Red Group with a win over Angelique Kerber on Friday, and the American could still advance with a defeat if the result of the other tie between Bertens and Osaka falls in her favour.
(Reporting by John O'Brien; editing by John Stonestreet)