Petra Kvitova struggled in the heat during her U.S. Open quarterfinal defeat against Flavia Pennetta.
Petra Kvitova struggled in the heat during her U.S. Open quarterfinal defeat against Flavia Pennetta.
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Pennetta's victory means Italy, for the first time, will have two women in the singles semifinals at the same grand slam tournament.
Pennetta's victory means Italy, for the first time, will have two women in the singles semifinals at the same grand slam tournament.
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Fifth seed Kvitova made a strong start, as she did in all four previous matches, by winning the first set 6-4.
Fifth seed Kvitova made a strong start, as she did in all four previous matches, by winning the first set 6-4.
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Pennetta was seeking to match her best grand slam result -- reaching the semis at Flushing Meadows two years ago.
Pennetta was seeking to match her best grand slam result -- reaching the semis at Flushing Meadows two years ago.
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The 33-year-old took advantage of Kvitova's high error rate as she defeated the two-time Wimbledon champion for the first time since 2010.
The 33-year-old took advantage of Kvitova's high error rate as she defeated the two-time Wimbledon champion for the first time since 2010.
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Kvitova announced before the U.S. Open that she has been diagnosed with mononucleosis -- known as "kissing disease" -- which causes chronic fatigue.
Kvitova announced before the U.S. Open that she has been diagnosed with mononucleosis -- known as "kissing disease" -- which causes chronic fatigue.
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Pennetta will next face world No. 2 Simona Halep (pictured) -- who beat two-time U.S. Open finalist Victoria Azarenka in a rain-hit match.
Pennetta will next face world No. 2 Simona Halep (pictured) -- who beat two-time U.S. Open finalist Victoria Azarenka in a rain-hit match.
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Halep won the opening set 6-3 against the former world No. 1.
Halep won the opening set 6-3 against the former world No. 1.
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Azarenka was wearing compression sleeves to protect her arms, having suffered an apparent allergic reaction to the material of her outfit in her previous match.
Azarenka was wearing compression sleeves to protect her arms, having suffered an apparent allergic reaction to the material of her outfit in her previous match.
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Azarenka leveled the match by winning the second set 6-4.
Azarenka leveled the match by winning the second set 6-4.
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However, play was halted in the third set, which Azarenka led 2-1, when rain arrived earlier than had been forecast.
However, play was halted in the third set, which Azarenka led 2-1, when rain arrived earlier than had been forecast.
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When they returned over an hour later, Halep rallied to win the decider 6-4.
When they returned over an hour later, Halep rallied to win the decider 6-4.
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