A one-under-par 70 was more than enough for the American, who finished on 13 under at Royal Liverpool.

On seven under par, world number three Jon Rahm finished tied for second with Sepp Straka, Tom Kim, and Jason Day.

Rory McIlroy finished on six under par, while Matthew Jordan and Tommy Fleetwood shared for fourth on four under.

Jordan has had a fairytale week, having started on the Royal Liverpool chipping green at the age of three and becoming a member at the age of seven.

The R&A awarded him the honor of playing the first tee shot on Thursday, and he birdied the last to post a one-under-par final round on Sunday, vaulting him into the top 10 and qualifying him for the Open at Royal Troon in Ayrshire next year.

“Normally, I just see players on TV and think to myself, ‘that’d be cool if that happened to me,'” he told BBC Sport.

“It was the perfect ending to what had been the most incredible week.”

Harman has also had a fairytale week. The 36-year-old, ranked 26th in the world, is only the third left-hander to win the Claret Jug, following in the footsteps of Bob Charles in 1963 and Phil Mickelson in 2013.

The triumph, which netted him £2.3 million, is only his third in his career and his first since 2017.

And he accomplished it by expertly charting his route around the links. He only walked into two bunkers all week, one on the 72nd, nailed 59 of 60 putts from within 10 feet, and had no three putts, all of which contribute to champions.

“I knew I had a six-shot lead on the 18th, and I was ready to putt it down that fairway,” he explained to BBC Sport.

“It’s what you dream about as a kid, to do it on the biggest stage.”

“I’ve always wanted to handle this trophy. It’s going to be difficult to pry it from my cold, dead fingers.”

“This golf course was a real test, it was set up so great – even with the weather,” said the champion, who promised to drink “a couple of pints” from the Claret Jug. The greens were immaculate, and the golf course was fantastic.

“I am overjoyed to be the champion. I appreciate all of the supporters, all of the kind messages, and all of the fans back home cheering me on. Thank you very much.”

Despite bogeys on the second and fifth holes, Harman’s advantage never fell below three, with the latter coming when he drove his ball into a gorse bush, dropping him to 10 under.

Rahm, who had birdied the sixth, was his closest contender at that point as the rain that had promised all week finally arrived and lasted for the day.

Harman reclaimed his lead with consecutive birdies on the sixth and seventh holes, while world number three Rahm slipped with a bogey on the ninth.

But Harman was out of sight for the majority of the day. Those in the rear were vying for second place.

Straka birdied the 16th to finish on eight under par, the lowest of any of the difficult holes. Harman was dropping a shot on the short 13th around the same moment, with his first missed putt from inside 10 feet of the week.

However, the American answered once more with consecutive birdies, putting an end to the chasing pack’s hopes.

Straka bogeyed the last to finish with a 69 and join South Korean Kim, who shot a four-under 67 with four birdies and an eagle.

Rahm birdied the last to tie for second with Australia’s Day, who made four birdies and two bogeys in his 69 as he moved up the leaderboard to earn his best Open Championship finish.

Cameron Young, Harman’s closest competitor, faded with a 73 and a five-under total, while Viktor Hovland also shot a 73 to finish three under.

‘I can’t be too upset.’

McIlroy had three consecutive birdies from the third to tie for second on six under, but a bogey on the 10th disappointed both the Northern Irishman and his thousands of fans, who were gathered under umbrellas as rain poured down on the Wirral peninsula all afternoon.

“It was a solid performance,” said the world number two, who finished in joint sixth place with Argentina’s Emiliano Grillo. “I was improving my score every day and felt like I was putting better.”

“I got off to a really good start, but it’s just hard to keep that going – as the leaderboard shows, no one was going low.”

“I’m usually right there when I tee it up.” “I can’t sit here and be too frustrated,” remarked the winner of the Scottish Open last week.

McIlroy finished with a 68, his 20th top-10 result in a major since winning the 2014 Open at Royal Liverpool.

Only ten players have won a major with more time between them than McIlroy’s 2014 US PGA Championship win and this Sunday’s Hoylake victory.

Between his US Open victories in 1952 and 1963, Julius Boros set a record of 11 years and nine days.

After a five-under-par 66 in round one, home favourite Fleetwood started the week on top of the leaderboard.

The 32-year-old from Southport, Merseyside, followed that with two level-par rounds and was enjoying a bogey-free Sunday until he came onto the 17th tee on six under.

The short par-three hole has been heavily criticized this week for its punitive run-off areas and bunkers, and Fleetwood fell victim to them, flying the green with his tee shot and finishing with a catastrophic triple-bogey six.

A birdie at the last delighted many in the fans, but his quest for his first major victory continues.

Lawrie Canter finished on two under par with fellow Englishman Alex Fitzpatrick, one shot ahead of Tyrrell Hatton.

Michael Stewart finished as Scotland’s top finisher. He was two shots off the lead after a 68 on Thursday and was one under par on Sunday. However, a final-round 76 dropped him down the standings to finish four over.

Christo Lamprecht of South Africa, who was joint leader on day one, was the only amateur to play all four rounds and finished 11 over par to win the Silver Medal.