- Maria Sharapova loses to Petra Kvitova in straight sets at the WTA Finals
- Sharapova needs to win her final group match to have any chance of progressing
- Serena Williams recovers from a bad defeat Wednesday to crush Eugenie Bouchard
- Caroline Wozniacki improves to 2-0 after downing Agnieszka Radwanska in straight sets
A day after world No. 1 Serena Williams suffered one of the worst losses of her career at the WTA Finals, second-ranked Maria Sharapova wasn't that much better.
Sharapova's hopes of reaching the semifinals in Singapore -- not to mention overtaking Williams as the year-end No. 1 -- are hanging by a thread following a 6-3 6-2 defeat to Petra Kvitova on Thursday.
But Williams rebounded in Thursday's last match by crushing an out of sorts Eugenie Bouchard 6-1 6-1.
Kvitova famously beat Sharapova at Wimbledon in 2011 to open her grand slam account but the Czech had lost five in a row to the U.S.-based Russian.
Sharapova hit six double faults and was broken five times as she fell to 0-2 in the White Group.
Never one for excuses, she refused to blame the result on fatigue two days after Caroline Wozniacki outlasted her in a grueling three-hour contest.
"I don't feel tired," Sharapova told reporters. "I'm happy to be here. I'm happy to be part of this event.
"It's easy to sit here and say, 'Yeah, I'm tired.' But that's not the way I feel or the way that I choose to speak."
Kvitova improved to 1-1 while the resurgent Wozniacki remained a perfect 2-0 after earlier topping Agnieszka Radwanska 7-5 6-3.
Sharapova -- who won her lone year-end title 10 years ago -- must now beat the 1-1 Radwanska on Friday to have any chance of advancing. But even a win won't guarantee a spot in the semifinals.
For Sharapova to become the year-end No. 1, she now has to win the tournament and hope Williams doesn't make the final.
"I still have a match ahead of me, and I will do my best to finish it on a good note," Sharapova said. "That's the only thing I can ask of myself."
Simona Halep routed Williams 6-0 6-2 in the Red Group on Wednesday, prompting the 18-time grand slam winner to say she was "embarrassed" with her performance.
She was far better versus a Bouchard who has done little since reaching the Wimbledon final.
"Yesterday was tough for me but I had to put it behind me," Williams was quoted as saying by the WTA. "My coach really helped me out and to focus on today, telling me that I'm still in the tournament, even though I felt like I was out of it after such a tough loss."
Bouchard escaped a 0-40 hole on serve in the first game but then lost 11 consecutive games to trail 6-1 5-0. The Canadian finished with an 0-3 record and didn't claim a set.
If Ana Ivanovic doesn't beat Halep -- who has already qualified for the semifinals -- in straight sets Friday, Williams and Halep progress to the last four.