US Open champion Zverev advances in Shanghai Masters third round. Shelton and Tiafoe beaten

SHANGHAI (AP) — Top-seeded Alexander Zverev let two match points slip in the second-set tiebreaker before winning 6-4, 6-7 (8), 6-3 against Quentin Halys at the ATP 1000 Shanghai Masters on Sunday.Zverev never gave up a break-point chance in a third-round match where the U.S. Open champion needed seven of his own just to break the 48th-ranked Frenchman’s service in the opening game.A 60th win on tour this season also was Zverev's fourth against Halys, including a late-night five-setter at Flushing Meadows in the second round.Earlier Sunday, U.S. Open finalist Ben Shelton was beaten 7-6 (5), 7-6 (3) by 21-year-old Frenchman Arthur Gea in the third round. The third-seeded Shelton, who won his first match in Shanghai on his 24th birthday, saw Gea convert his first match-point chance in the second-set tiebreaker.Seventh-seeded Francis Tiafoe also lost, after having a match point in the decisive tiebreaker, to Alejandro Davidovich Fokina, who won 7-6 (4), 4-6, 7-6 (6).Ninth-seeded Alex de M