Nathan Chen rued two mistakes in his free routine but still became the first man this millennium to win four straight Skate America titles.
The 21-year-old phenom only managed a double Salchow from a planned quad and missed a triple Axel but finished nearly 25 points ahead of Vincent Zhou in Las Vegas.
World champion Chen, unbeaten since finishing fifth at the 2018 Winter Olympics, is the first man to win four golds on the bounce at the event since Todd Eldredge from 1994 to 1997.
"I made quite a few big mistakes," said Chen, head and shoulders above the field in a competition behind closed doors and restricted to US athletes due to COVID-19.
"They were things that I shouldn't have made mistakes on, but it is what it is. I'll move forward from here.
"At the end of the day, I know what my job is and I know what I want to accomplish. With these mistakes, I have things to focus on moving forward.
"I'm just thrilled to be here at this competition, so thankful to everyone who has been involved, to bring us together and how smoothly it went so that skaters just could focus on skating."
Chen held an overnight lead with a score of 111.17 in his short program and nailed five quad jumps across both routines to prevail with a total of 299.15.
His free routine was set to music by Phillip Glass and brought in 187.97 points, enough to win the first top-level competition in nine months.
Zhou - who won bronze behind his compatriot at the 2019 World Championships - won the first Grand Prix medal of his career and Alaskan Keegan Messing took bronze.
Meanwhile Mariah Bell, who like Chen is coached by Rafael Arutunian, defied a fall on her free skate to claim the biggest title of her seven-year singles career.
The 24-year-old clung on to gold despite falling on a triple lutz, the 76.78 points from her excellent short program helping her past Olympian Bradie Tennell by 1.66 points.
Bell is a veteran in a discipline where the reigning US champion, Alysa Liu, is 15 and would be the oldest figure skater to represent USA at an Olympics in nearly a century if she makes Beijing 2022.
"I hate it but I love it when people talk about age," she said.
"I would never use my age as any kind of an excuse. There's no reason why me being 24 would make anything harder. I should be more in tune with my body and have a better understanding."
Madison Hubbell and Zachary Donohue won their third successive ice dance gold at Orleans Arena, mirroring the three-peat pulled off by Sochi Olympic champions Meryl Davis and Charlie White.
And Alexa Scimeca Knierim and Brandon Frazier, both national champions with other partners, claimed pairs victory on their top-level debut together.