Roger Federer faced Tommy Robredo ten times already and won every single match. Maybe Robredo was due for an upset. In a shocker, No. 19 Robredo defeated No. 7 Federer in straight sets, 7-6, 6-3, 6-4, at the 2013 U.S. Open. As a result, Robredo will advance to the quarterfinals of the Open for the first time in his career. 

Even though the crowd was heavily in favor of Federer, Robredo was the one who was less prone to mistakes as Federer committed 43 unforced errors. Following his victory, Robredo seemed just as shocked as the crowd, saying "I won. That's amazing, isn't it? I beat the best guy of all-time in a great stadium like this in the US Open. I'm delighted. It's unreal.”  

Robredo may face Rafael Nadal next, who he's 0-6 against, but judging from his stunning victory over Federer, anything is possible. 

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[via Eye On Sports]