MADRID, SPAIN - MAY 08: Maria Sharapova of Russia in action during her match against Eugenie Bouchard of Canada on day three of the Mutua Madrid Open tennis at La Caja Magica on May 8, 2017 in Madrid, Spain. (Photo by Clive Rose/Getty Images)
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Maria Sharapova's debated return to US Open
Serena Williams' coach, Patrick Mouratoglou, weighs in on Maria Sharapova's controversial return to the U.S. Open via a wild-card entry.
01:39 - Source: CNN
Athletes and doping 16 videos
MADRID, SPAIN - MAY 08: Maria Sharapova of Russia in action during her match against Eugenie Bouchard of Canada on day three of the Mutua Madrid Open tennis at La Caja Magica on May 8, 2017 in Madrid, Spain. (Photo by Clive Rose/Getty Images)
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Maria Sharapova's debated return to US Open
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LONDON - JUNE 27: Maria Sharapova of Russia serves against Nathalie Dechy of France during the seventh day of the Wimbledon Lawn Tennis Championship on June 27, 2005 at the All England Lawn Tennis and Croquet Club in London. (Photo by Mike Hewitt/Getty Images)
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Canadian sprinter Ben Johnson sets a world record in the 100 metres final at the 1988 Summer Olympics in Seoul, 24th September 1988. (Photo by Tony Duffy/Getty Images)
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