Ben Shelton picked the perfect setting to win his first match against Carlos Alcaraz, beating the Spaniard in a marathon five-set thriller 7-6, 1-6, 3-6, 6-1, 6-7 to secure a place in the US Open semi-finals.
Alcaraz won a tight first set and later levelled the clash at two sets apiece despite struggling with unforced errors. But he was unable to get over the finish line as Shelton raised his level when it mattered to prevail.
Shelton, 23, produced a stunning ace to seal the win, taking the final set tiebreak 10-7.
He will face fellow American Frances Tiafoe for a place in Sunday's final after Tiafoe staged a stunning comeback to eliminate Alex Michelson over five sets.
For Alcaraz, the quarter-final defeat completes a disappointing summer. He won the Australian Open to begin the year but subsequently missed four months due to a wrist injury that kept him out of the French Open and Wimbledon.
An uncharacteristic 53 unforced errors in this match undoubtedly contributed to his exit.
The seven-time major champion arrived at Arthur Ashe Stadium with a 13-0 Grand Slam record against US men but found Shelton tough to break down in a match that began at 11.05pm on Tuesday and finished at 3.33am on Wednesday.
The Spaniard clinched a tight first-set tiebreak and looked to have all the momentum, but some uncharacteristic sloppiness allowed Shelton to breeze through the next set before the American tightened his grip on the quarter-final by taking the third.
Alcaraz vomited into a towel during the break but went toe-to-toe with Shelton for 12 games before his opponent closed out the shock win after four hours and 28 minutes.
For Shelton, it was the biggest win of his career, and he thanked the New York crowd for staying out to witness the latest-finishing match in tournament history.
"For me, it's always about the people in the crowd, whether it's my coaches and my team, all of my family and friends or the city of New York that showed up tonight until 3am, that's what kept me going tonight," he said in his post-match interview.
"It is incredible. I always say that this is the greatest sports city in the world; this is the greatest stadium in the world. I'm just hoping my best friend and sister don't have to be at work at 6am. It would be huge from their employers to let them have the day off!
"I'm so grateful, so blessed. God has blessed me in so many ways for me to be in front of you guys tonight.
"It is an absolute honour to share the court with Carlos. I cherish every moment that I have out here."
Tiafoe's show of sportsmanship for Michelson
Tiafoe recovered from two sets and a break down to beat US compatriot Michelsen 5-7, 3-6, 7-5, 6-3, 7-6, reaching the semi-finals for a third time in a thrilling fightback.
The 11th seed Tiafoe appeared to have lost all the magic of his early campaign before wresting the momentum in the third set and clinching it with a forehand winner to the deafening cheers of fans at the Arthur Ashe Stadium.
Michelsen had flown under the radar in his deepest major run but earned respect on the biggest stage of American tennis with 21 aces, and Tiafoe cut his own celebration short to comfort the 22-year-old in an emotional embrace.
"I slowly, slowly started getting my rhythm there," said Tiafoe. "He's a hell of a player, man."
The two brought their best tennis to a nerve-searing final set, where the crowd sprang to their feet as Tiafoe sealed the win before offering words of encouragement to a weeping Michelsen.
"I don't think anyone else could have made me cry in that moment, to be honest," said Michelsen.
"Frances, he's such a good guy and he said a lot of personal things and just kind of got to me."
The moment of good sportsmanship attracted almost as much attention as Tiafoe's monster comeback, with the veteran able to sense the sting of defeat better than most after exiting Wimbledon and Roland Garros this year in five-set sagas.
"I understand the moment," Tiafoe said. "He was definitely crying on my shoulders. Yeah, we just had some words for each other, and that was it."
The Shelton-Tiafoe winner will be just the second US man to appear in a US Open final in 20 years.
Taylor Fritz lost the 2024 championship match to Italy's Jannik Sinner. The last US player to capture the men's singles crown at Flushing Meadows was Andy Roddick in 2003.
