The last time Roger Federer lost a set in the first round of a US Open was 2003, to Jose Acasuso. The last time he went five sets in a US Open opener was in his first Flushing main draw, against Peter Wessels in 2000.
Yet there he was, under the lights in Arthur Ashe Stadium on Day 2, locked in a five-set tussle that no one saw coming, against a man nearly half his age but, for large stretches of this night, his shot-making equal.
It was a back-and-forth affair from the start. Tiafoe broke Federer at the jump and held his serve throughout to claim the first set. Federer re-established control in the second and third sets, winning each effortlessly to take hold of the match. And then, suddenly, the tables were turned, Tiafoe cruising through an easy fourth frame in a tidy 24 minutes to force the decider on the strength of his buggy-whip forehand and Road Runner wheels.
The fifth set was high drama. Federer served for the win and held a match point on his racquet, but was, stunningly, broken. But the Swiss, though never at his best on this evening, summoned his good-enough when he needed it, breaking back in the next game to earn a 4-6, 6-2, 6-1, 1-6, 6-4 victory that thrilled the capacity crowd until the very last shot.