Nadal Wins Epic Over Thiem; del Potro Advances Past Isner to Reach US Open Semifinals

US Open—New York, New York

Quarterfinal results:

(1) Rafael Nadal Defeats (9) Dominic Thiem 06 64 75 67(4) 76(5)
(3) Juan Martin del Potro Defeats (11) John Isner 67(5) 63 76(4) 62