Trinidad and Tobago denied United States a seventh successive world 4x400 metres relay title when Lalonde Gordon overhauled Fred Kerley on the final straight to win a breathtaking final at the World Athletics Championships on Sunday.
The U.S led for most of the race and appeared to be on course for another win after Michael Cherry ran a strong third lap to extend their lead before handing the baton to Kerley.
But Gordon gave chase and ran a superb final lap for the Caribbean islands, catching the American on the home straight to give Trinidad their first world title in this event and add to the list of upsets at the championships.
It was just reward for Lalonde who was part of the Trinidad team which took bronze on the same track at the London Olympics five years ago and won silver at the Beijing World Championships in 2015.
Jereem Richards, bronze medallist in the 200 metres, and Machel Cedenio also kept them in contention in the second and third legs as Trinidad claimed their first and only gold of the championships.
Martyn Rooney put up a brave chase for Britain but was unable to haul in the leading pair and the hosts took bronze.
Trinidad's time of 2:58.12 was the fastest this year.
"We knew the U.S. team are always strong and we were prepared for that," Cedenio said.
"I think it was the best experience of all my career. We came third in 2012 in the national record. Now it is gold and I cannot ask for more."
The United States, who are also Olympic champions, last failed to win the world title in Paris in 2003.
"I got the lead for the fourth leg," Cherry said. "Silver is a good medal. You never expect to lose coming into a race. We gave all we had.”