Alexander Zverev claims first US Open after four-set battle with Ben Shelton

<ul><li><p>No 1 seed wins 6-3, 7-6 (2), 5-7, 6-2</p></li><li><p>American’s hopes dashed in tense final</p></li></ul><p>For a passing moment at the end of a rugged third set, hope sprung anew for Ben Shelton. He had been outserved and