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Maria Sharapova, the Russian star and former world No. 1, fell to American teenager Melanie Oudin in the third round of the 2009 US Open in one of the biggest upsets in tennis history. The 7-5, 6-4 victory propelled 17-year-old Oudin, a wild card entry from Marietta, Georgia, into the spotlight and made her an overnight sensation in the tennis world.