NEW YORK (Reuters) - Unseeded South African Lloyd Harris stormed into his first Grand Slam quarter-final with a crushing 6-7(6) 6-4 6-1 6-3 victory over American Reilly Opelka on Monday.

The 24-year-old Harris, whose previous best performance at a major was his run to the third round of the Australian Open earlier this year, will next face fourth seed Alexander Zverev for a place in the semi-finals.