Ben Shelton advanced to his first Masters quarterfinal by beating fourth-ranked Jannik Sinner 2-6, 6-3, 7-6 (5) on Tuesday.
The 21-year-old American, a semifinalist at the U.S. Open, had 15 aces as his serve improved throughout the match.
“I had a lot of belief in my ability to serve and hang tough and to make it deep in sets,” Shelton said. “My serve wasn’t working that well in the first set, I felt that he was really on top of me. I really started to find my groove and had one of my best serving days in the second and third sets.”
The 19th-seeded Shelton will next play Sebastian Korda, who advanced to his second Masters quarterfinal with a 7-5, 7-6 (6) victory over Francisco Cerundolo.
Fresh from his upset over third-ranked Daniil Medvedev in the previous round, Korda held off a late rally by Cerundolo and saved a set point in the second-set tiebreaker.
“I’m just super happy with the way I played in the tiebreak. I stayed calm when he was a couple of mini-breaks up and I’m just happy with how I played overall,” Korda said.
Eighth-seeded Casper Ruud lost to Fabian Marozsan 7-6 (3), 3-6, 6-4. The 82nd-ranked Marozsan will next play either 16th-seeded Hubert Hurkacz or Zhang Zhizhen in his maiden Masters quarterfinal.