Jake Wightman produced the run of his life to become the first British man to win a 1500metre world title since Steve Cram in 1983.
In a quick race commentated on inside the stadium by his father and coach Geoff, the pace slowed marginally on the penultimate lap.
Olympic champion Jakob Ingebritsen had set the tempo at the front but Wightman, who had finished a disappointing 10th in Tokyo having had aspirations for a medal, passed the Norwegian halfway around the last lap and kicked clear on the home straight.
For a moment, it looked like the Norwegian would reel him in but Wightman had enough speed to hold him off as Spain’s Mohamed Katir rounded off the podium.
Wightman’s father said over the speaker system inside the stadium: “That’s my son and he’s world champion,” as his wide-eyed offspring looked stunned by his shock win.
“I had such a disappointing year in Tokyo last year,” he said after taking gold. “I just knew here to take the pressure off. I was running for my life in the home straight. Jakob’s so good that I knew he’d come past at some point but at least I’d given it a go.
“The closer I got to the line the more likely I felt like that was going to happen. I’ve given so much getting to this point. My mum’s in tears, she probably will be for another week. I can’t believe I’m world champion, it’s crazy.”
Josh Kerr, who had won a medal behind Ingebrigtsen at the Olympics had to make do with fifth in the push for the medals in a season’s best of 3:30.60.
“Obviously, I’m disappointed to not come away with a medal but Jake Wightman is a true champion and I’m really proud of what he achieved today,” said Kerr. “I know he’s been determined to get this one so it’s awesome for him. That was the run of his life.
“It was world record pace for the first 400m. Maybe I wasn’t fit enough to run and go win it from the front but I can’t be disappointed with that because I gave everything I had today.”
Defending world champion Dina Asher-Smith clocked a season’s best time of 21.96seconds as she booked her placed in the finals of the 200metres in a blanket finish in a tight semi-final alongside Olympic champion Elaine Thompson-Herah.
Asher-Smith, one of five women to dip below 22s, was the fourth quickest qualifier as 100m silver medallist Shericka Jackson topped the times with a 21.67.
And Asher-Smith, who had agonisingly finished the 100m in fourth place, said: “I am really happy with that. I knew that each of these three semi-finals, the field is so wide open and the quality is so high.
“We knew we had to run this very well so I was really happy to get second. I didn’t actually know if I came first or third so I was just waiting. I’m happy that I’ve got a day’s break so I can rest, recuperate, focus and get ready to go again, just a bit faster.”
Her British teammates Nethaneel Mitchell-Blake and Joe Ferguson, however, failed to make the finals of the event as they finished fourth and seventh respectively in their semi-finals.
