No. 17 Frances Tiafoe continued a strong start by American men at the US Open, defeating Yoshihito Nishioka of Japan, 6-3, 7-6 (6), 6-3 on Monday to reach the second round at Flushing Meadows.
Tiafoe, a two-time semifinalist in New York, has won 15 US Open matches since 2022, passing Jannik Sinner for most among men during that span. He's the only man to reach the quarterfinals or better each of the past three years.
"Most years coming into the Open, I haven't really won many matches at all. But I get out there, I just feel different. I'm moving great, hitting the ball pretty well," Tiafoe said. "It's a different type of feeling. Playing on a court named after Arthur Ashe, it's awesome, and it's the biggest arena we have. It's super electric."
Tiafoe won 84% of his first-serve points -- including a perfect 12-of-12 in the third set -- against Nishioka, who has now lost 13 of his last 14 tour-level matches since the start of March.
"He's a tough opponent. He's got a great backhand, and he can extend points. He really makes you beat him," Tiafoe said.
Tiafoe joined No. 4 Taylor Fritz and No. 6 Ben Shelton in reaching the second round. Up next for him is an all-American matchup with Martin Damm, who beat 17-year-old Darwin Blanch 6-3, 6-4, 6-4.
Blanch, who trains at the JC Ferrero Academy in Spain and has practiced a lot with Carlos Alcaraz, was given a wild card into the tournament by winning this year's USTA National Boys' 18s at Kalamazoo, Michigan.
Tiafoe has had great success playing his compatriots at the US Open, with his five wins against Americans since 2021 second only to Sinner (7).
They're all chasing the same prize: the first Grand Slam singles trophy for an American man since Andy Roddick triumphed in New York in 2003. That's quite a ways away at this point, though, especially considering that Sinner and No. 2 Carlos Alcaraz have combined to win each of the past seven major titles.
"I think this is the group to do it. Someone is going to do it pretty soon here," Tiafoe said. "Guys are knocking on the door. I played Fritz here in the semis. He made the final.
"Ben has been going deep in Slams very consistently. Fritz made semis at Wimbledon. ... Guys are beatable, man. The door is open."
In other men's singles results, Brazilian teenager Joao Fonseca, who turned 19 on Thursday, won his US Open debut, defeating Miomir Kecmanovic 7-6 (3), 7-6 (5), 6-3 in front of a raucous crowd of his countrymen.
Fonseca is the third Brazilian man in the Open era to win a match at all four majors in one year, joining Gustavo Kuerten (1999) and Thomaz Bellucci (2010).
No. 5 Jack Draper, playing his first match since losing to Marin Cilic at Wimbledon and subsequently being diagnosed with bone bruising in his left arm, battled past qualifier Federico Agustin Gomez 6-4, 7-5, 6-7 (7), 6-2.
Also on Monday, American Alex Michelsen, the No. 28 seed, lost in four sets to Argentina's Francisco Comesana, while No. 22 Ugo Humbert of France fell to Australian Adam Walton 6-4, 7-6 (4), 5-7, 6-1.
No. 24 Flavio Cobolli, a quarterfinalist at Wimbledon, had to go the distance but reached the second round with a 7-5, 4-6, 6-4, 3-6, 6-3 win over fellow Italian Francesco Passaro.
Also prevailing in five sets was American Jenson Brooksby, who beat Aleksandar Vukic 6-3, 6-7 (4), 6-4, 3-6, 6-4.
Holger Rune, the No. 11 seed, won 6-3, 7-6 (4), 7-6 (2) against Botic Van De Zandschulp, who famously stunned Alcaraz in the second round of last year's US Open.
In the night session, No. 12 Casper Ruud eased past Sebastian Ofner 6-1, 6-2, 7-6 (5) on Louis Armstrong.
ESPN Research and The Associated Press contributed to this report.