A par at 17 left him needing a birdie at the last to break McIlroy's record and after striping a 379-yard drive down the fairway on the long par-5 finishing hole, he left a 3-wood just short of the green and his ensuing chip left him some 40 feet from the hole.
"I thought it was a fantastic round of golf, given what we were dealing with to start the day", the 23-year-old said.
"I didn't exactly get my dad a card, so this works". I felt like I did a lot of good things, especially in the first round, executing my game plan. "I've been there a handful of times and had some good finishes, but I'm looking forward to getting the job done".
In a field that saw nine players start the day within four shots of the lead, American Brooks Koepka emerged victorious to win his first major title at the 117th U.S. Open on Sunday at Erin Hills in Wisconsin.
Fleetwood, who was hoping to follow in the footsteps of 1970 victor Tony Jacklin and 2013 champion Justin Rose, held a share of second place on 11 under par alongside Americans Brooks Koepka and Justin Thomas.
"I'm not saying the older guys are out by any means, but I think we're making our presence a little bit more known". "The conditions were so tough". The world number 50 headed to the clubhouse on 12 under, one ahead of Thomas, Brooks Koepka and England´s Tommy Fleetwood. Harman was dominant on the greens this week, but just didn't have the firepower to topple Koepka. "But there's way too many holes out here where one bad shot could be a double bogey quickly".
Overnight leader Harman appeared nervous early on but rescued pars on the opening two holes before reclaiming a share of the lead thanks to a 29-foot birdie putt on the third.
South Korea's Kim Si Woo was one behind Fowler on nine under after also shooting a 68, while three players - Patrick Reed (65), Russell Henley (67) and Charley Hoffman (68) - were on eight under.
It also marks the seventh consecutive major that has crowned a first time victor.
It was the first time the top three players in the world failed to make the cut.
The gusts tapered off from the morning, but they still were making Erin Hills play more hard than it had all week. But Koepka birdied 14, 15 and 16 to pull away. And then he made birdie on the next hole.
After his birdie at 14, Koepka wasn't aware of Harman's bogey back at 13. He went out in 33 after a par at the ninth but gave one back at the 10th, his first bogey on the back nine all week.
But the American then paid the price for an over-aggressive birdie attempt on the 10th which sailed past the hole leaving an awkward putt to save par.
"To be honest, the par save on 13 built some confidence, " Koepka said.
Like Harman, Thomas couldn't match Koepka's final-round mastery, which came on Father's Day.
Fleetwood, who had made the cut in just one of his previous seven major appearances, finished alone in fourth on 11 under following a final round of 72, with Rickie Fowler, Bill Haas and Xander Schauffele a shot further back in fifth.
T9. Justin Thomas (-8): The lingering memory from Thomas' 2017 U.S. Open will always be his 63 on Saturday, not only because of its historical relevance but because things got real shaky on Sunday in a hurry as he played his way out of contention.