- WTA Championships
Stosur replaces Kvitova in Istanbul

Defending champion Petra Kvitova has been forced to withdraw from the WTA Championships with a viral illness.
The Czech looked out-of-sorts as she was beaten 6-3 6-2 by Agnieszka Radwanska in her opening match on Tuesday.
She will be replaced by first alternate Sam Stosur for the remaining White Group round-robin matches against Maria Sharapova and Sara Errani.
"I was nervous the whole match," Kvitova said after her match on Tuesday. "My fingers and my legs weren't moving. I'm disappointed in myself. I made a lot of errors in the match today; it wasn't good tennis from my side."
However, Kvitova is expected to have recovered in time to lead Czech Republic for the defence of their Fed Cup title next week.
She joins Lucie Safarova, Andrea Hlavackova and Lucie Hradecka for the clash against Serbia in Prague on November 3 and 4 after captain Petr Pala named the same side that beat Italy 4-1 in the semi-finals.
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