Zheng Jie and Victoria Azarenka retire from their fourth-round matches
Out of four matches played to wrap up the fourth round of the Australian Open, two were finished with players retiring. To my great disappointment, Zheng Jie and Victoria Azarenka had to give up their fight for the quarterfinal spot because of health problems.
The No.22 seed Zheng sprained her left wrist and was forced to retire trailing 4-1 in the first set against eighth seed Svetlana Kuznetsova.
As for Azarenka, No.13 seed, she won the first set against seed No.2 Serena Williams 6-3. In the
second set, trailing Williams 4-2, Azarenka was visibly suffering under the hot conditions, and with tears in her eyes retired from the match due to dizziness and gastrointestinal illness.
In the other two matches, Dementieva, the fourth seed, remained undefeated in 2009, crushing No.18 seed Dominika Cibulkova 6-2 6-2, while Carla Suarez Navarro won an all-Spanish encounter against No.21 seed Anabel Medina Garrigues 6-3 6-2. Suarez Navarro upset one of the favorites for the title Venus Williams in the second round, coming back from 5-2 down in the third set and saving match points to win the match.
American Serena Williams will meet Kuznetsova in the quarterfinals, and is 4-1 against the Russian, while Dementieva will play Suarez Navarro for the first time in her career. (source: Sony Ericsson WTA Tour, photos: Getty Images)

Svetlana Kuznetsova beat Zheng Jie in a tight two-setter to set up a clash with top seed
Oh Ana, you haven't had a winning streak for so long. When was the last one, at Wimbledon? And even there you
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Sixth seed Serena Williams 
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