NEW YORK (AP) — Japan's Kei Nishikori advanced to the fourth round of the U.S. Open on Saturday with a 6-4, 6-2, 6-3, victory over Leonardo Mayer of Argentina. The 10th-seeded Nishikori, who has not made it past the fourth round in five previous U.S. Open appearances, showed no sign of a big toe injury that hampered his preparations for Flushing Meadows. Nishikori faces the winner of the match between fifth-seeded Milos Raonic and Victor Estrella Burgos.Read more on NewsOK.com