Dominika Cibulkova of Slovakia dumped top seed Vera Zvonareva out of the Kremlin Cup in MOscow on Friday.
Mixed fortunes for top seeds in Moscow
Dominika Cibulkova of Slovakia dumped top seed Vera Zvonareva out of the Kremlin Cup in Moscow on Friday.
The eighth seed overcame the world number five 4-6 6-4 6-4 despite struggling with a knee injury she suffered in her previous match.
Both players received medical timeouts during the clash, with Zvonareva struggling with a shoulder problem in the deciding set.
The Russian rushed into a 40-0 lead as she served to stay in the match at 4-5 but was unable to convert on each occasion as Cibulkova broke to clinch the win.
Pain
Zvonareva admitted afterwards that she probably shouldn't have competed the match due to her injury.
"I started having pain in my shoulder in the second set and I started thinking about it and was afraid it would get worse," the world number five said.
"I've tried to fight through the pain but just couldn't get it done. I probably should have stopped.
"I have this bad habit - I often keep on playing even when I have an injury and it doesn't do me any good."
Cibulkova, the world number 20, will take on Russia's Elena Vesnina in the semi-finals after she received a walkover following the withdrawal of Marion Bartoli through illness.
It meant Poland's Agnieszka Radwanska claimed the last available place at the season-ending WTA Championship in Istanbul.
Bartoli had to win the Moscow tournament to qualify for the year-end event in Turkey at Radwanska's expense, the Pole having gone out in the second round.
"I'm so happy to finally qualify for the Championships as one of the top eight singles players," Radwanska said on the WTA website.
"Just a few weeks ago I didn't think I had a chance of qualifying and I am now so happy to end my season in Istanbul."
There was another shock result later in the afternoon when sixth seed Svetlana Kuznetsova was hammered 6-1 6-2 by Kaia Kanepi of Estonia.
And on a poor day for the home players, Lucie Safarova of the Czech Republic reomoved Vera Dushevina 6-4 6-4 to earn a clash with Kanepi for a place in the final.
Edged
In the men's draw, Top seed Janko Tipsarevic of Serbia claimed a 6-4 6-2 win over Russian sixth seed Dmitry Tursunov.
Tipsarevic's fellow countryman Viktor Troicki, the second seed, edged out America's Alex Bogomolov Jr in a match of three tie-breaks.
Troicki triumphed 7-6 (8/6) 6-7 (1/7) 7-6 (7/1) in three hours 38 minutes.
Fourth-seeded Nikolay Davydenko, playing in front of a home crowd, swept aside German qualifier Michael Berrer 6-3 6-2, while France's Jeremy Chardy knocked out another German, Philipp Kohlschreiber 6-4 6-3.