Del Potro Advances to U.S. Open Final When Nadal Retires With Injury

By DAVID WALDSTEIN Sports https://ift.tt/2Cx9lvS
United States Open (Tennis), Tennis Juan Martin del Potro reached his first Grand Slam final since 2009, winning the first two sets, 7-6 (3), 6-2, before Rafael Nadal stopped the match with an apparent knee injury.