Britain's Josh Kerr stunned Norway's Olympic champion Jakob Ingebrigtsen to take 1500m gold at the World Championships in Budapest.
Kerr, Olympic bronze medallist in Tokyo, timed his surge for gold to perfection inside the final 200m.
The 25-year-old clocked a season's best three minutes 29.38 seconds to make his first podium at a World Championships.
It comes one year after Ingebrigtsen suffered defeat by Briton Jake Wightman in similar circumstances in Eugene.
Kerr let out an almighty roar as he crossed the line, celebrating with the crowd and embracing his parents in the stands with a crown on his head and a gold medal proudly hanging from his neck.
"It's been a long time coming," the Scot said.
"It's quite an overwhelming experience but I'm so proud of myself and of my team and my family that got me here.
"I didn't feel like I ran the best race. I just threw my whole 16 years of this sport in that last 200m and didn't give up until the end."
Ingebrigtsen, meanwhile, appeared crestfallen as history repeated itself.
The 22-year-old led from the front for much of the race before once again being denied by a gutsy finish from a British athlete, Kerr breaking his rival in the final 50m.
Ingebrigtsen held on for silver in 3:29.65 ahead of compatriot Narve Gilje Nordas (3:29.68), while Britain's Neil Gourley finished ninth in 3:31.10.
Kerr earned GB a fourth medal of the championships, and second gold, following in the footsteps of Katarina Johnson-Thompson's heptathlon triumph.
Kerr emulates Wightman to stand on top of the world
Evidently full of confidence coming in to the championships, Kerr had stated his belief that Ingebrigtsen - unbeaten this season and boasting the fastest time of 2023 - was "very beatable".
And, as 2022 champion Wightman watched on, the Scot emulated his Edinburgh Athletics Club team-mate in spectacular fashion.
Ingebrigtsen had been determined to upgrade last year's silver and took control on the second lap - but once again was powerless to respond as Kerr moved level and then refused to fade away.
The reigning world 5,000m champion came into the championships unbeaten, running the fourth-fastest 1500m of all time in July, and was a heavy favourite for gold.
Kerr had run his two fastest times since Tokyo earlier this season, but Ingebrigtsen was in unrelenting form as he built towards correcting his 2022 loss.
While his talent is undeniable, Norway's versatile star will rightly be concerned about the manner in which world gold was once again ripped from his grasp, with another Briton adding his name to the list of contenders at Paris 2024.
Kerr demonstrated his ability to produce elite level performances on the global stage when he won his Olympic bronze in 2021, becoming the first British man to win a medal over 1500m at a Games since 1988.
Battling illness when he finished fifth at last year's Worlds, he backed up that breakthrough medal here with a superbly managed run.
Warholm reclaims world title as pole vaulters share gold
Men's 400m hurdles world record holder Karsten Warholm reclaimed his title with a dominant victory after his 2022 hopes were hindered by injury.
Warholm, who finished seventh last season after struggling with a hamstring injury in the run up to the meeting, had shown signs of a return to his devastating best in 2023 by producing two of the five fastest performances of all time.
The Norwegian clocked 46.89 seconds to clinch his fourth global title ahead of Kyron McMaster of the British Virgin Islands (47.34) and American Rai Benjamin (47.56).
In the women's 400m final, Marileidy Paulino of the Dominican Republic took gold in 48.76 ahead of Poland's Natalia Kaczmarek and Barbadian Sada Williams.
Britain's Molly Caudery also shone in a thrilling women's pole vault final which saw Australian Nina Kennedy and American Katie Moon share gold.
Kennedy and Moon agreed to share the title after both athletes cleared 4.90m but neither could make 4.95m after three attempts.
A delighted Caudery, 23, produced a personal best with a clearance over 4.75m to finish fifth on her first appearance at a global championships.
Team-mate Anna Purchase qualified for the hammer throw final in 11th with a 71.31m best attempt but Charlotte Payne (69.57m) did not.
GB's Cindy Sember was unable to reach the women's 100m hurdles final with a sixth-placed semi-final finish in 12.97 secs, while Megan Keith and Amy Eloise-Markovc failed to qualify from the women's 5,000m heats, which were pushed back from the morning session because of extreme heat with temperatures well above 30C.
Markovc finished 11th in 15:13.66 in her heat - during which Sifan Hassan and 1500m gold medallist Faith Kipyegon engaged in an unnecessary sprint finish - while Keith was 14th in 15:21.94 in her race.
Aimee Pratt missed out on the women's 3,000m steeplechase medal race, finishing seventh in her heat in 9:26.37