- WTA Championships
Serena set for Kvitova battle in Istanbul
Serena Williams has been drawn in the same group as Petra Kvitova for the season-ending WTA Championships in Istanbul.
The world No. 1 and defending champion will take on the 2011 winner, and is bidding to become the first player since Justine Henin six years ago to successfully defend her crown.
Williams and Kvitova will be joined in the Red Group by Agnieszka Radwanska and Angelique Kerber.
"It's a tough group. I have to be ready. That's the thing about this tournament and why it's so tough, you have to be ready from the first match on," Williams, who has won the French and US Opens and eight other titles in 2013, said.
Kvitova, who lifted the trophy at Wimbledon in the same year she triumphed in Istanbul, expects difficult encounters.
"Both of the groups are very tough and I don't think you can choose anyone who you think is weaker. This means that it's going to be a big fight every day, every match," the Czech said.
Meanwhile, world No. 2 and Australian Open champion Victoria Azarenka is in the White Group alongside Li Na, Sara Errani and Jelena Jankovic.
And on her opponents, Azarenka said: "It's the best eight players in the world. Anybody who is here is going to be a challenge. It's exciting, and I can't wait to play all those players."
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