Having beaten Andy Murray en route to his first Grand Slam semi-final at this year's French Open and now overcome arguably the greatest tennis player of all time, the 6ft 5ins right-hander is building quite some reputation.

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The French Open, the second grand slam tournament of the tennis season, begins in Paris on May 24.

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Another golfer, Australia's Adam Scott, has recently rekindled his romance with glamorous Serbian tennis star Ana Ivanovic, the 2008 French Open champion.

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But Serena Williams, Isner and the Bryans appear poised for breakout springs in Europe, which if all falls right for American tennis could mean singles contenders at the French Open and a competitive Davis Cup semifinal tie in Spain.

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Among other sports stars, he said in an interview that he had worked with Sara Errani, an Italian tennis player who on June 8 won the women's doubles title at the French Open and a day later played in the women's single final only to lose to Maria Sharapova.

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Karatantcheva was suspended from tennis for two years in 2006, after she tested positive for nandrolone at the 2005 French Open when she was 15.

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