There’s leaving it late, and then there’s what Ben Shelton and Carlos Alcaraz just served up at the U.S. Open.

The American star ultimately outdueled the defending champion in the latest ever finish at the tournament, a 3:33 a.m. thriller in front of a raucous New York crowd.

The five-set victory takes Shelton to the semifinals, where he will face fellow American Francis Tiafoe.

Alcaraz saw his 18-match winning streak in Grand Slam tournaments ended in a clash that lasted 4 hours, 28 minutes.

Carlos Alcaraz celebrates winning the fourth set.Matthew Stockman / Getty Images

The highlight-filled quarterfinal was played under the lights after a day of marathon contests at Flushing Meadows.

The match swung back and forth, with 8th seed Shelton winning the second and third sets after losing the first on a tie break.

Second seed Alcaraz, who missed most of the season with a wrist injury, won the fourth set 6-1 to set up a grueling fifth and final set.

The pair traded blows but ultimately couldn’t be separated until the final set tiebreaker, which Shelton won 10-7.

Shelton during the quarterfinal.Patrick Smith / Getty Images

The Shelton-Alcaraz epic now stands as the latest finish in the history of the New York tournament, which is increasingly known for its overnight duels.

That honor had previously been held by another Alcaraz match, against his rival at the top of the sport Jannik Sinner, which finished at 2:50 a.m in the 2022 quarterfinals. That victory helped Alcaraz on the way to his first U.S. Open title.

No U.S. men’s player has won a Grand Slam since Andy Roddick in New York in 2003. There is now guaranteed to be an American in Sunday’s final.