Osaka regains composure, overcomes Kostyuk en route to next round of U.S. Open

Two-time Grand Slam champion Naomi Osaka eventually figured out a way to turn a tight one into a runaway and beat 18-year-old Marta Kostyuk 6-3, 6-7 (4), 6-2 by claiming the final five games at Flushing Meadows.