Tiafoe trailed Medvedev 1-6 in career head-to-head before ‌Sunday - his only victory coming at the team ‌competition Laver Cup - but cracked the code when it mattered to ‌him the most, repeatedly striking near the net with ‌surgical precision.

"Daniil has been so good, he's beaten me so many times. This is the first time I've beaten him in a ‌regular match," said the 11th seed. "Everything is ⁠feeling really good. I'm ‌coming forward, I'm having fun."

Tiafoe will next play compatriot Alex Michelsen.

Down ​5-6 in the opening set, Tiafoe broke his opponent from the baseline to force the tiebreak, where ​he ran up on the net to control the early tempo and never looked back.

He sent a forehand down ⁠the line to break ​the Russian in the fifth game of the second set and survived a fantastic cat-and-mouse exchange on the third set point with a perfectly placed backhand volley that even Medvedev ‌applauded.

The pair traded early breaks before settling into a tense, final-set battle, where Tiafoe did some of his best work playing serve-and-volley tennis, with both players making scarce few mistakes.

Medvedev's double fault was the only flaw in an otherwise sensational final tiebreak, where Tiafoe outfoxed his rival in a rapid-fire exchange at the net to save set point and get the crowd on their feet.

Tiafoe is now unbeaten ‌through 10 appearances at Louis Armstrong Stadium, which plays second ​fiddle at Flushing Meadows to the stately Arthur Ashe ‌court but has clearly earned the affection of the charismatic American fan favorite.

"It's been amazing playing on this court, the energy has been amazing," said Tiafoe, who basked in the cheers after forcing Medvedev into an ⁠error from the baseline ⁠on match point. "It's like ‌the people's court."