Cameron Norrie proved far too strong for troubled Frenchman Benoit Paire as he eased into the second round, while Dan Evans joined him with a clinical display.
Paire is not short on talent, with his backhand one of the best around, but his effort has often been called into question and he barely seemed to try during the first and third sets in sweltering conditions.
Norrie lost just 17 points in the two sets combined either side of a highly competitive second and wrapped up a 6-0 7-6 (7-1) 6-0 victory in an hour and 40 minutes.
- Raducanu to surprise us again? Serena, Murray & Norrie's US Open hopes
- Murray makes perfect start to US Open campaign
- US Open: Order of Play I Women's Draw I Men's Draw I Scores & Schedule
The British No 1 is playing as a top-eight seed at a Grand Slam for the first time and is firmly in the conversation as a contender for the title, particularly after his run to the Wimbledon semi-finals.
It would be hard to find two tennis players with more different attitudes to their sport and Norrie was focused from the start while Paire made 16 unforced errors - twice the number of points he won - and hit only one winner in a first set that lasted less than 20 minutes.
The second was a different story and, after a brief delay when a spectator collapsed in the stands, Paire broke the Norrie serve to leave himself serving for the set at 5-3.
However, Norrie broke back straight away, dominated the tie-break and, with Paire barely jogging around the court in the third, quickly completed the job.
"It's tricky, especially with how Benoit plays," Norrie said when asked about playing against someone who at times did not appear to be trying to win.
"Because he looks like he's not really there and he can come up with a few good shots and a few big returns. In that third set he was love-30 a couple of times, 15-30, and that's when he's very dangerous. I think he's an exciting player to watch and he's a really nice guy."
He later added: "It's unfortunate, I think he played a little bit too quick, and at the end of the day I went out and did my job."
Norrie, who improved his win-loss record to 42-19 for the year, will next face Portuguese Joao Sousa who came out on top in a roller-coater match against American Mackenzie McDonald, winning 1-6 7-6 (7-4) 7-6 (7-4) 6-3.
Paire admits Norrie defeat could be last match of his career
The Frenchman had packed his bag ready to leave the court prior to coming out to serve at 0-5 in the third and won just 17 points combined across the two love sets.
Paire has been open about his mental struggles on the court and, speaking to L'Equipe, he revealed he is considering not returning to tennis.
He said: "I was leading 5-3, I could have taken the second set, it would have done me good in the head, but my demons came back again, the double faults, and it starts all the time the same.
"We'll see what happens. I'm not sure to continue the season, maybe stop there and see if I resume next year.
"Even at Grand Slams, I find it difficult to fight. I hope one day to find a motivation, something that will make me love tennis. Right now, I'm the happiest when I'm at home and the unhappiest when I'm in the tournament.
"I don't even want to get angry on a tennis court anymore. It's not a good sign - if I don't get angry, it's because I don't care."
- Serena Williams: The career of a tennis icon
- Can Kyrgios claim US Open glory and become King of New York?
- Get Sky Sports | Download the Sky Sports App
Evans joins Norrie with impressive performance
Evans swept aside Jiri Vesely to become the fifth British player through to the second round.
With defending champion Emma Raducanu still to play, this is already the joint-most British players to reach the second round in New York since 1981, with Evans joining Andy Murray, Norrie, Jack Draper and Harriet Dart.
Evans reached the fourth round last year and arrived at Flushing Meadows buoyed by a run to the semi-finals of the ATP Tour event in Montreal earlier this month.
And he was ruthless against Czech Vesely, wrapping up a 6-4 6-1 6-1 victory in an hour and 55 minutes in brutally hot conditions.
"I played well," said Evans. "It was a tricky match really. I'm not massively fond of playing lefties so it was good. He's got a good serve so it can be a difficult match for me but I got out of it well and played some good tennis."
In other matches, third seed Carlos Alcaraz was given a battle by Sebastian Baez before the Argentinian began to struggle in the heat and retired trailing 7-5 7-5 2-0.
Don't forget to follow us on skysports.com/tennis, our Twitter account @skysportstennis & Sky Sports - on the go! Available to download now on - iPhone & iPad and Android