Paying scant regard to the form book, Agnieszka Radwanska took advantage of an errant Kvitova display to run out a surprisingly comfortable 6-2, 6-3 win over Petra Kvitova.
Much of the talk in regards to the White Group after the draw centered on the heavyweight clash between Kvitova and Maria Sharapova. However, on Tuesday evening, Radwanska and Caroline Wozniacki, who earlier defeated Sharapova, put their names into the conversation in emphatic fashion.
Refreshed and revitalized following a few weeks back home in Krakow, Radwanska raced out of the traps. She manufactured a couple of opportunities on the Kvitova serve before deservedly breaking through with some characteristically opportunistic play in the sixth game.
With Kvitova struggling to settle into any sort of rhythm, Radwanska sensed her chance, breaking once more to take the opening set. This setback appeared to fire up the Czech, who came out at the start of the second with a renewed sense of purpose to build a 3-2 lead.
Radwanska, though, was not to be denied, praying on the Czech's second serve to take the next four games and with it the match.
"She's a great champion and playing some amazing tennis, especially the last few months, so I'm really happy with that win," Radwanska said. "There's only eight of us here, so you have to go out and try your best, otherwise you're not going to win. And I'm very happy with the way I played tonight."
It was only the second time in seven attempts that Radwanska had gotten the better of Kvitova - fittingly, her only other win also came at the WTA Finals, two years ago in Istanbul.
For Kvtova, defeat leaves facing an uphill battle to make the semifinals and places even greater importance on her clash with Sharapova.
"Yeah, I think probably we were both favorites in our matches and of course in our group," Kvitova said. "That's what happens in tennis. I know that Caro beat her in US Open, so she knew it would be difficult.
"I thought that I can beat Aga as well today, but everybody is really up for this week and the matches can all go both ways."
Radwanska went into Singapore lacking a little match sharpness, having failed to go beyond the quarterfinals of a WTA event since winning Montréal in August. But competing a the season finale is old hat to the Pole, who is making her fourth straight appearance.
"I think I knew how to prepare for this tournament from other years," Radwanska said. "So I think I did everything right this year and I am really feeling good and ready to go."