Over the hardest three laps of his life, Cole Hocker clung on with the stub­bornness of a mule. Then, in an ­Olympic 1500m final for the ages, he kicked like one.

It took the 23-year-old ­American past the fading Tokyo gold medallist Jakob Ingebrigtsen of ­Norway. Then, in an extraordinary last few yards, Britain’s world ­champion Josh Kerr. And suddenly, and without warning, a 37-1 underdog from Indianapolis had shaken up the world.

Related: Hocker has last laugh after Kerr and Ingebrigtsen’s tiresome war of words | Jonathan Liew

Marvin Hagler’s extraordinary fight with Tommy Hearns was dubbed “The War”. This men’s Olympic 1500m final was the track and field equivalent. It was a full-on slugfest almost from the gun, only with a twist that nobody expected.

As Hocker crossed the line in an Olympic record of 3min 27.65sec, Kerr clung on for silver in 3:27.79 – a time that also broke Mo Farah’s ­British record. Another American, Yared Nuguse, claimed bronze in 3:27.80. Ingebrigtsen, who had been a strong pre-race favourite, faded to fourth.

“I never thought I had won,” Kerr said. “It was electric in there so it was difficult to tell who was around. I told you guys we were going to put on an Olympic 1500m final that would last for generations and hopefully we did that today.”

The tale of the tape beforehand suggested that the 23-year-old ­Ingebrigtsen had the edge. He was the Olympic champion, the fastest man in the world this year, and last month set a personal best of 3:26.73 – more than two seconds quicker than Kerr and nearly three clear of Hocker.

But the Norwegian also had an achilles heel: his sprint finish which Kerr had exploited in beating him to world championship gold in Budapest last year.

Ingebrigtsen knew he had to change tactics. And there was no hanging about as he launched an attack after just 100m in an attempt to set his opponents’ legs and lungs on fire. The first 400m came and went in 54.82sec. The 800m mark was in 1min 51sec. The pace was so crazy it was quicker than when Hicham El Guerrouj set his world record in 1998.

“The big thing today was always going to be: weather the storm early,” said Kerr. “I thought: ‘He is going to try and pull us into deep waters early and see who could survive.’ I had to take a few punches.”

With 600m remaining ­Ingebrigtsen was about five metres clear of ­Kenya’s Timothy Cheruiyot in second, with Kerr a couple of metres back in third. But by the time the bell rang the Briton was closing. It led to a ­thrilling last lap, with Ingebrigtsen being stalked by Kerr, Hocker and Nuguse as Cheruiyot fell back.

First Hocker tried to strike on the inside, only for the Norwegian to block him off. Then Kerr attacked and took the lead. For a moment, a golden horizon awaited him. But Hocker had enough in his legs to deliver a final gut-punch. The numbers showed that the American had run the final 300m in 39.6sec – off a brutal pace.

“It’s an unbelievable feeling,” Hocker said. “I just felt like I was getting carried by the stadium and God. My body just kind of did it for me. My mind was all there and I saw that finish line.

“Winning gold was my goal this entire year. I wrote that down and I repeated it to myself even if I didn’t believe it. My performances showed me that I was capable of running 3:27, whatever it took. I knew I was a medal contender, and I knew that if I got it right, it would be a gold medal.”

But you had to feel for Kerr too. Such was the determination to win ­Olympic gold in Paris that he ran twice on Christmas Day, eight miles in the morning followed by another three after a heavy dinner.

Over the past few months, the 26-year-old had also leaned out like a boxer making weight – with every meal and training session geared towards 8.50pm local time on 6 August 2024. He really could not have done any more.

“At 600m to go I felt I had quite a lot left and coming off that last bend I got pushed out a little bit,” he said. “I was able to come round Jakob but there is a lot of running left at that point. It is so difficult to keep track of everything that is going on in the last 100m.”

Related: ‘I can’t walk away disappointed’: Josh Kerr still proud after 1500m silver

Afterwards Kerr denied he had spent too much time focusing on Ingebrigtsen, their bitter rivalry leading to so many eyeballs on this contest. And while he did question the Norwegian’s approach, he did so with respect. “It was a brave strategy and it didn’t quite work but it made for a great race,” he said.

Meanwhile Hocker admitted that all the talk before Ingebrigtsen versus Kerr had played into his hands. “I kind of told myself that I’m in this race too,” he said. “If they let me fly under the radar, then so be it. I think that might’ve just been the best.”

As for Ingebrigtsen, he conceded he may have pushed the pace too hard because he felt so good at halfway. “I can only blame myself. It’s a difficult game, balancing your energy. This was a risk I was going to take.”

It led to a thrilling and unpre­dictable ride. Just not the result either he or Kerr ultimately wanted.