Defending champion Rafael Nadal survived an epic US Open quarter-final confrontation to defeat battling ninth seed Dominic Thiem 0-6, 6-4, 7-5, 6-7 (4/7), 7-6 (7/5) and reach the semi-finals for the seventh time.

In a gripping 4-hour 49-minute contest which concluded at 2.04 a.m. on Wednesday, world number one Nadal won through to keep his bid for a fourth title in New York and 18th Grand Slam crown on track.