Agnieszka Radwanska of Poland holds aloft the Billie Jean King Trophy after defeating Petra Kvitova of Czech Republic in the title match of the WTA Finals.
Agnieszka Radwanska of Poland holds aloft the Billie Jean King Trophy after defeating Petra Kvitova of Czech Republic in the title match of the WTA Finals.
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Kvitova of Czech Republic reacts to a point against Maria Sharapova in the way to a surprise victory over the Russian in the WTA Finals.
Kvitova of Czech Republic reacts to a point against Maria Sharapova in the way to a surprise victory over the Russian in the WTA Finals.
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Sharapova of Russia looks dejected after slipping to a shock defeat to Kvitova in the semifinals.
Sharapova of Russia looks dejected after slipping to a shock defeat to Kvitova in the semifinals.
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Radwanska ended the hopes of Spain's Garbine Muguruza in the semifinals at the WTA Finals.
Radwanska ended the hopes of Spain's Garbine Muguruza in the semifinals at the WTA Finals.
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Muguruza beat Kvitova 6-4 4-6 7-5 at the WTA Finals in Singapore to win the White Group and progress to the semifinals.
Day Six —
Muguruza beat Kvitova 6-4 4-6 7-5 at the WTA Finals in Singapore to win the White Group and progress to the semifinals.
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But it wasn't all bad news for Kvitova, the two-time Wimbledon champion ...
Day Six —
But it wasn't all bad news for Kvitova, the two-time Wimbledon champion ...
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She joined Muguruza in the last four when Lucie Safarova, pictured, topped Angelique Kerber in straight sets, 6-4 6-3.
Day Six —
She joined Muguruza in the last four when Lucie Safarova, pictured, topped Angelique Kerber in straight sets, 6-4 6-3.
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Kerber's week began well when she downed Kvitova but then the German lost to Muguruza and Safarova.
Day Six —
Kerber's week began well when she downed Kvitova but then the German lost to Muguruza and Safarova.
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In Saturday's semifinals, Sharapova, pictured, played Kvitova and Muguruza faces Radwanska.
Day Six —
In Saturday's semifinals, Sharapova, pictured, played Kvitova and Muguruza faces Radwanska.
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That about sums it up for Simona Halep. She lost to Radwanska on Thursday and was eliminated at the WTA Finals.
Day Five —
That about sums it up for Simona Halep. She lost to Radwanska on Thursday and was eliminated at the WTA Finals.
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A frustrated Halep, seen here with coach Darren Cahill, fell 7-6 (7-5) 6-1. The Romanian was the highest ranked player in the field at No. 2.
Day Five —
A frustrated Halep, seen here with coach Darren Cahill, fell 7-6 (7-5) 6-1. The Romanian was the highest ranked player in the field at No. 2.
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Sharapova knew she made the semifinals even before she played Flavia Pennetta but still beat the Italian 7-5 6-1, rallying from 4-2 down in the first.
Day Five —
Sharapova knew she made the semifinals even before she played Flavia Pennetta but still beat the Italian 7-5 6-1, rallying from 4-2 down in the first.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Sharapova finished at 3-0 in the Red Group and progressed with Radwanska. Pennetta, meanwhile, played the final match of her career.
Day Five —
Sharapova finished at 3-0 in the Red Group and progressed with Radwanska. Pennetta, meanwhile, played the final match of her career.
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Kvitova bounced back from her opening defeat at the WTA Finals in Singapore by beating fellow Czech Lucie Safarova 7-5 7-5 on Wednesday.
Day Four —
Kvitova bounced back from her opening defeat at the WTA Finals in Singapore by beating fellow Czech Lucie Safarova 7-5 7-5 on Wednesday.
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Kvitova has now beaten her friend eight times in a row. Next month they will line up together against Russia in the Fed Cup final, seeking to give the Czech Republic a fourth title in five years.
Day Four —
Kvitova has now beaten her friend eight times in a row. Next month they will line up together against Russia in the Fed Cup final, seeking to give the Czech Republic a fourth title in five years.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Kvitova will play unbeaten Spanish second seed Muguruza in her final White Group match. The 22-year-old has two wins from two after beating Angelique Kerber 6-4 6-4 in Wednesday's second match.
Day Four —
Kvitova will play unbeaten Spanish second seed Muguruza in her final White Group match. The 22-year-old has two wins from two after beating Angelique Kerber 6-4 6-4 in Wednesday's second match.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Sixth seed Kerber, who would have reached the semis with victory over Muguruza, faces Safarova in her closing match.
Day Four —
Sixth seed Kerber, who would have reached the semis with victory over Muguruza, faces Safarova in her closing match.
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Sharapova celebrates after beating top seed Halep 6-4 6-4 in their second Red Group round-robin match in Singapore.
Day Three —
Sharapova celebrates after beating top seed Halep 6-4 6-4 in their second Red Group round-robin match in Singapore.
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Halep could have qualified for the semifinals with victory, but the Romanian lost seven out of eight games from 4-4 in the opening set and the Russian held off her late fightback.
Day Three —
Halep could have qualified for the semifinals with victory, but the Romanian lost seven out of eight games from 4-4 in the opening set and the Russian held off her late fightback.
MOHD FYROL/AFP/AFP/Getty Images
Pennetta signs autographs for fans after defeating Radwanska 7-6 (7-5) 6-4 in Tuesday's earlier Red Group match. Italy's U.S. Open champion kept her semifinal hopes alive ahead of her closing match against Sharapova.
Day Three —
Pennetta signs autographs for fans after defeating Radwanska 7-6 (7-5) 6-4 in Tuesday's earlier Red Group match. Italy's U.S. Open champion kept her semifinal hopes alive ahead of her closing match against Sharapova.
Julian Finney/Getty Images AsiaPac/Getty Images
Radwanska led 5-3 in the opening set, and the Polish fifth seed saved three match points before her second defeat in three days.
Day Three —
Radwanska led 5-3 in the opening set, and the Polish fifth seed saved three match points before her second defeat in three days.
Clive Brunskill/Getty Images AsiaPac/Getty Images
Spain's rising star Muguruza opened her White Group campaign with a 6-3 7-6 (7-4) win against Safarova of the Czech Republic on Monday.
Day Two —
Spain's rising star Muguruza opened her White Group campaign with a 6-3 7-6 (7-4) win against Safarova of the Czech Republic on Monday.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Safarova beat the 22-year-old in this year's French Open quarterfinals in their only other meeting, but the world No. 9 was sidelined by a debilitating bacterial infection after her first-round defeat at the U.S. Open.
Safarova beat the 22-year-old in this year's French Open quarterfinals in their only other meeting, but the world No. 9 was sidelined by a debilitating bacterial infection after her first-round defeat at the U.S. Open.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Kvitova, who has also struggled with health issues this year, lost 6-2 7-6 (7-3) to Germany's Angelique Kerber in their opening White Group match.
Day Two —
Kvitova, who has also struggled with health issues this year, lost 6-2 7-6 (7-3) to Germany's Angelique Kerber in their opening White Group match.
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Kerber had lost her previous four clashes with her fellow left-hander, who won the tournament in 2011 when it was held in Istanbul.
Kerber had lost her previous four clashes with her fellow left-hander, who won the tournament in 2011 when it was held in Istanbul.
ROSLAN RAHMAN/AFP/AFP/Getty Images
Sharapova triumphed against Radwanska on Sunday in her first completed match since the Wimbledon semifinals. The world No. 4 pulled out with an arm injury during her return in Wuhan last month.
Day One —
Sharapova triumphed against Radwanska on Sunday in her first completed match since the Wimbledon semifinals. The world No. 4 pulled out with an arm injury during her return in Wuhan last month.
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Sharapova battled Radwanska for nearly three hours on Sunday before triumphing 4-6 6-3 6-4.
Day One —
Sharapova battled Radwanska for nearly three hours on Sunday before triumphing 4-6 6-3 6-4.
Clive Brunskill/Getty Images AsiaPac/Getty Images
World No. 2 Halep, meanwhile, needed just 70 minutes to thrash Pennetta 6-0 6-3.
Day One —
World No. 2 Halep, meanwhile, needed just 70 minutes to thrash Pennetta 6-0 6-3.
Julian Finney/Getty Images AsiaPac/Getty Images
Pennetta, who will retire at the end of this season, was unable to regain the form that gave her a straight-sets victory over the 24-year-old in the U.S Open semis.
Day One —
Pennetta, who will retire at the end of this season, was unable to regain the form that gave her a straight-sets victory over the 24-year-old in the U.S Open semis.
Clive Brunskill/Getty Images AsiaPac/Getty Images
WTA Finals: Radwanska triumphs

Story highlights

Kvitova and Radwanska advance

Win semis at WTA finals

Sharapova shocked in Singapore

Nadal and Federer in Basel final

CNN  — 

Petra Kvitova and Agnieszka Radwanska advanced to the title match at the WTA Finals Saturday after upset victories in semifinal matches in Singapore.

Fomer Wimbledon champion Kvitova had claimed just a single win in the round-robin phase, but proceeded to dispatch five-time grand slam champion Maria Sharapova 6-3 7-6.

The first semifinal had seen Poland’s Radwanska battle past Spanish world number three Garbine Muguruza 6-7 6-3 7-5.

Both Sharapova and Muguruza had advanced to the knockout stage by winning their groups with 3-0 records and were heavily favored to be battling it out for the prestigious end of season trophy.

he first time.

“I didn’t expect this, for sure,” Kvitova admitted after her stunning victory.

“I had two losses in my group, and I couldn’t really believe I would play the semifinals. And I knew Maria would be strong today – she played so well in the round robin group, so I expected a really tough match.

“But I knew I had the game to beat her, and that I really had to keep trying today,” the Czech star told the official WTA website.

Kvitova had big success on the Sharapova service, breaking the Russian three times in the first set and then recovered from 5-1 down in the second, winning five straight games before claiming the tiebreak.

Kvitova will be bidding for her second success in the tournament, while Radwanska is in her first final at the sixth time of asking.

“I have no words to say really,” Radwanska said.

“I didn’t know if I could come back after that first set, but I think it was a great match from the beginning until the end, so many rallies and a lot of running. I’m just so glad I could win this match in the end.”

It was her 50th win on the WTA Tour this season, but she has a losing 6-2 record against Kvitova.

Consolation for rising star Muguruza will be an appearance in the doubles final alongside fellow Spaniard Carla Suarez Navarro. They will face top-ranked pair Martina Hingis and Sania Mirza in Sunday’s final.

On the men’s ATP Tour, old rivals Roger Federer and Rafael Nadal will contest the final of the tournament in Basel.

Nadal underlined his recent improvement with a 6-4 7-6 win over Richard Gasquet of France in their semifinal.

Federer, bidding for his seventh title at his home event, later beat American Jack Sock 6-3 6-4 in just an hour.