Frances Tiafoe produced one of the most remarkable recoveries of this year's US Open on Tuesday, fighting back from two sets down and trailing 3-0 in the fifth to defeat fellow American Alex Michelsen 5-7, 3-6, 7-5, 6-3, 7-6 (10-6) in a match lasting nearly four hours and forty minutes at Arthur Ashe Stadium in New York. The victory puts Tiafoe, the 11th seed, into the semifinals of the year's final Grand Slam for the third time in his career.

Michelsen, ranked 46th in the world and just 22 years old, had been the only player in the men's draw yet to drop a set and looked firmly in control for the majority of the contest. Serving at 5-4 in the third set with a chance to close out the match, the young Californian succumbed to nerves, striking two consecutive double faults that allowed Tiafoe to break back. From that pivotal moment, the match shifted decisively. Tiafoe won three straight games to take the third set and carried that momentum into the fourth and fifth, eventually securing the match tiebreak 10-6 with an ace at 135 mph. At the net after the final point, a tearful Michelsen — who fell to 0-6 in fifth-set matches — sobbed on Tiafoe's shoulder in a poignant moment that underlined the emotional weight of the occasion.

Tiafoe was candid about his sluggish start.