The eighth seed struck 11 aces, won 83% of his first-serve points and did not face a break point in a 6-2, 6-3, 6-4 win, his cleanest performance of the tournament.
“I thought I played well. Good, clean match. Happy to be back in the quarters here,” Shelton said afterwards.
“I didn’t do anything perfect, by any means. But because I was so focused and able to repeat what I was doing point after point, I felt I was able to get into a lot of return games and put pressure on.”
Stefanos Tsitsipas, the 28-year-old former world No. 3 and a two-time Grand Slam finalist, took a medical time-out at 6-2, 5-2 and could not drag the match back.
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The rematch Alcaraz has already won three times
Carlos Alcaraz reached his fifth US Open quarter-final earlier the same day with a 6-4, 6-3, 6-4 win over Tommy Paul. The Spaniard has now won 18 Grand Slam matches in a row.
Alcaraz leads Shelton 3-0 in their career meetings, none of them at Flushing Meadows. Their most recent match came in the fourth round at Roland Garros last year, a 7-6(8), 6-3, 4-6, 6-4 win for Alcaraz.
The defending champion is playing his first Grand Slam since a wrist injury sidelined him from April.
“I’m really happy to see where my level is right now. Just really happy about everything,” Alcaraz said.
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Shelton’s serve keeps him alive; the second serve is the crack
Their Roland Garros meeting was the closest of the three, decided over four sets in which Shelton took a set off Alcaraz. His serve remains the weapon that keeps him in any match with Alcaraz, as it did in Paris, but second-serve consistency and shorter rallies are what Alcaraz preys on when they slip.
‘Fireworks on Tuesday’
“I think it’s going to be fireworks on Tuesday. I hope you guys come back because I’m going to be ready,” Shelton told the Arthur Ashe crowd.
The quarter-final is scheduled on Arthur Ashe Stadium for Tuesday, 8 September.
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