Eighth-seeded Ben Shelton overpowered former world number three Stefanos Tsitsipas 6-2, 6-3, 6-4 on Sunday to book a US Open quarter-final date with defending champion Carlos Alcaraz.
Shelton -- riding high after a strong August that included a title at the ATP Montreal Masters, where he didn't drop a set -- dominated on serve.
The American blasted a dozen aces and never faced a break point in a match lasting just one hour and 52 minutes.
Shelton put 71 percent of his first serves in play and won 84 percent of those points.
"I was focused today," said Shelton, a 2023 US Open semi-finalist. "I played a complete match from start to finish."
Shelton powered through the opening set in 31 minutes, breaking Tsitsipas on the way to a 3-0 lead and breaking again to pocket the set.
He seized control of the second set with a break for 4-2, setting up his chance with a delicate drop shot to end another thumping baseline rally.
A forehand winner down the line had put Shelton up 5-2 when Tsitsipas called for the trainer.
He engaged in a lengthy conversation with the physio before receiving medication as Shelton became increasingly restive.
Tsitsipas then held at love, but Shelton was on the move again and closed out the set in the next game with an emphatic forehand winner.
He bagged another early break in the third set and cruised home.
Now he awaits Alcaraz, the seven-time Grand Slam champion who opted to make the US Open his first tournament back from a four-month injury layoff.
The Spaniard delivered his most convincing display of the tournament in a 6-4, 6-3, 6-4 victory over American Tommy Paul, and Shelton said it would take "special tennis" to beat him.
"I think the level that he's been playing at is really, really impressive," Shelton said. "I think it's going to be fireworks on Tuesday night."
It was a disappointing ending for Tsitsipas, a two-time Grand Slam finalist who hadn't made the second week of a major in more than two years.
The Greek has been in resurgent form this season, playing pain free after battling back trouble last year.
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