Key Biscayne's Crandon Park Tennis Center is the epicenter of tennis this week, with the Sony Ericsson Open in full swing until Sunday. And in the heat of athletic furor, no one makes more hilarious faces than tennis players -- and no one more than repeat offender Rafael Nadal. Check out this year's faces of mesh, whether etched with terror, effort, or utter confusion, on the likes of Andy Roddick, Serena Williams, Maria Sharapova and Andy Murray:
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