Reached the quarterfinals of the US Open for the first time.
Playing at the Arthur Ashe Stadium, the 24-year-old defeated Nadal 6-4, 4-6, 6-4, 6-3 in a full three hours, 31 minutes.
After claiming the first set and losing the second, Tiafoe made a stunning comeback to clinch the thirdIn a tight fourth set, the Spaniard scored first to lead 3-1.
He swung freely and held his nerve, cruising off five straight games to seal a historic win
Francis Tiafoe said on Monday evening, his biggest victory so far
The loss finished the Spaniard's offered for a record-expanding 23rd significant singles title.
Nadal was 31-2 in majors against the Americans entering Monday's match