After a thrilling three-man fight down the back nine at The Country Club, Fitzpatrick fired a two-under-par 68 to finish on six-under-par 274 and defeat Americans Scottie Scheffler and Will Zalatoris by one stroke.
“I’m going to say it because I won but I hit some unbelievable shots coming down the stretch and that’s what I work for,” Fitzpatrick said.
With perseverance, Fitzpatrick delivered his first professional US victory for a long-sought major trophy.
“It’s what you grow up dreaming of,” Fitzpatrick said. “It’s something I’ve worked so hard for for such a long time. There was a big monkey on my back trying to win over here and everyone, all they ever talked about was that. To do it as a major for my first win - there’s nothing better.”
World number 18 Fitzpatrick, who won the 2013 US Amateur at The Country Club, matched Jack Nicklaus as the only US Open and US Amateur winners on the same course, the US legend doing the double at Pebble Beach.
“It means the world,” Fitzpatrick said of the achievement.
The 27-year-old from Sheffield, who shared fifth last month at the PGA Championship for his best prior major result, sank a stunning 48-foot birdie putt at the 13th hole to grab a share of the lead.
At the 15th, Fitzpatrick blasted out of the right rough to just inside 19 feet and rolled in a tension-packed putt to reach 6-under and lead by two thanks to a Zalatoris bogey.
“Got a couple of nice breaks on 15 and took advantage of it and that’s what it took in the end,” Fitzpatrick said.
After birdies by top-ranked Masters champion Scheffler at 17 and Zalatoris on 16, Fitzpatrick clung to a one-stroke lead at the 18th tee.
The Englishman sent his tee shot into a left fairway bunker, but blasted a magnificent approach to 18 feet and two putted for par.
“I hit a 3-wood into the bunker and if there was one shot I’ve struggled with this year that I do not want it’s a fairway bunker shot,” said Fitzpatrick.
“I guess ability just took over. It’s one of the best shots I’ve hit of all time. When I saw it leave the sand and felt the strike I couldn’t have been happier.”
Zalatoris had a 14-foot birdie putt to force a playoff but when he missed, the record US$3.15 million (B111mn) top prize went to Fitzpatrick.
“Matt’s shot on 18 is going to be shown probably for the rest of US Open history,” Zalatoris said.
“I walked by it and thought that going for it was going to be ballsy, but the fact that he pulled it off and even had a birdie look was just incredible. So hats off to him.”
Fitzpatrick has had a workout program to boost his driving distance for the past two years, boosting his shotmaking courage.
“I absolutely backed myself 110%,” he said. “I feel like I can compete against anyone out here, particularly over the last two years as I’ve got longer. Hopefully this is the first step in getting even better.”
Japan’s Hideki Matsuyama, the 2021 Masters champion, fired the best round of the week, a bogey-free 65, to finish fourth on three-under 277.
Four-time major winner Rory McIlroy and two-time major champion Collin Morikawa shared fifth on 278 while second-ranked Spaniard Jon Rahm, the defending champion, shared 12th on 281 after a closing 74.
Scheffler fired a final-round 67 while Zalatoris, now a three-time runner-up in nine major starts, and third-ranked McIlroy each closed on 69 and seventh-ranked Morikawa, the reigning British Open champion, shot 66.
“Tip of the hat to Fitzy,” Scheffler said. “He’s hitting the ball really well and has been knocking on the door for a long time. He definitely deserves this win.”