Samantha Stosur booked her place in the quarter-finals of the Dubai Duty Free Championships with a 6-1 6-7 6-1 victory over Lucie Safarova.

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World number one Victoria Azarenka has been forced to withdraw from the Dubai Duty Free Championships.

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It was a bad day for the seeds at the Whirlpool Monterrey Open as three of the six ranked players suffered first-round exits.

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Top seed John Isner had to dig deep to see off Gilles Muller at the Regions Morgan Keegan Championships in Memphis.

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Fourth seed Marina Erakovic records a convincing win over Evgeniya Rodina in Memphis.

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Eighth seed Juan Ignacio Chela crashed out of the Copa Claro as he slipped up against Albert Ramos.

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Frenchman Richard Gasquet needed just over an hour to dispatch Japan's Go Soeda in straight sets at the Marseille Open.

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Sixth seed Marion Bartoli crashed out of the Dubai Tennis Championships after losing in straight sets to China's Shuai Peng.

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Seeds Stanislas Wawrinka and Kei Nishikori progressed through the first round of the Copa Claro.

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Jelena Dokic suffered a first-round defeat in the Whirlpool Abierto Monterrey tournament in Mexico.

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Ivan Ljubicic had to dig deep to beat wild card Florent Serra in three sets to reach the second round of the Open 13.

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Jelena Jankovic beat Petra Cetkovska to progress in the Dubai Duty Free Championships .

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Britons Elena Baltacha and Heather Watson both bowed out in Memphis on Monday.

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Wimbledon champion Petra Kvitova has pulled out of this week's Dubai Duty Free Championships.

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Milos Raonic successfully defended his title at the SAP Open in San Jose after he beat Denis Istomin 7-6 (7/3) 6-2 in the final.

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