Singapore (SportsNetwork.com) - In an epic battle of former world No. 1s, U.S. Open runner-up Caroline Wozniacki upset French Open champion Maria Sharapova in round-robin action at the season-ending $6.5 million WTA Finals.
The eighth-seeded Wozniacki outlasted the second-seeded Sharapova 7-6 (7-4), 6-7 (5-7), 6-2 in 3 hours, 13 minutes in Tuesday's first match on the hardcourts at Singapore Indoor Stadium.
After taking the 74-minute first set in a tiebreak, Wozniacki had chances to close it out in straight sets, going up 5-3 in the second and then serving for the match.
Sharapova fought back to claim the second stanza via tiebreak, only to see Wozniacki take control in the third.
"I'm feeling a little tired," Wozniacki said in her on-court interview. "But it was a great match. The first one is always tough, getting your rhythm and getting used to everything out there, but in the third set I felt like I really stepped it up and really started being aggressive and going for my shots more.
"And the crowd was absolutely unbelievable today -- thank you all for coming out!"
Sharapova captured the WTA Finals title in 2004 and is a two-time runner-up at the event, while Wozniacki was a finalist in 2010.
Another Day 2 result saw sixth-seeded Agnieszka Radwanska surprise third- seeded Wimbledon champ Petra Kvitova 6-2, 6-3.
"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."
Kvitova was the WTA Finals champ three years ago.
Wednesday's round-robin matches will pit current world No. 1 Serena Williams against fourth-seeded French Open runner-up Simona Halep and fifth-seeded Wimbledon runner-up Eugenie Bouchard versus seventh-seeded former top-ranked star Ana Ivanovic.
Williams has captured this prestigious eight-player tournament four times, including the last two years in Istanbul. The American great, who beat Li Na in last year's finale, is also a two-time Finals runner-up.
Williams (1-0) leads this week's four-player Red Group, which also features Halep (1-0), Bouchard (0-1) and Ivanovic (0-1). Sharapova (0-1) heads up the four-woman White Group, which also features Kvitova (0-1), Radwanska (1-0) and Wozniacki (1-0).
