WASHINGTON, DC - AUGUST 01: Juan Martin Del Potro of Argentina returns against Ryan Harrison during the Citi Open at the William H.G. FitzGerald Tennis Center on August 1, 2013 in Washington, DC. ... more 
WASHINGTON, DC - AUGUST 01: Juan Martin Del Potro of Argentina returns against Ryan Harrison during the Citi Open at the William H.G. FitzGerald Tennis Center on August 1, 2013 in Washington, DC. (Photo by Matthew Stockman/Getty Images) less 
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Getty Images | Photo By Matthew Stockman / Getty Images
Thu, Aug 1, 2013 6:09 PM EDT