Aug 31, 2016; New York, NY, USA; Milos Raonic of Canada serves against Ryan Harrison of the United States (not pictured) on day three of the 2016 U.S. Open tennis tournament at USTA Billie Jean King National Tennis Center. Harrison won 6-7(4), 7-5, 7-5, 6-1. Mandatory Credit: Geoff Burke-USA TODAY Sports