The 38-year-old had won every men’s kata title at the event since 2008 and after reaching the final with ease this year, he had been widely fancied to triumph again.

But it was not to be at Arena Roberto Duran Sports Hall, Diaz beaten by American Ariel Torres, a former Pan American bronze medallist.

On a day of finals, that was one of four gold medals seized by United States across the divisions.

Their first came in the women’s kumite under 68 kilogram event, where former World Combat Games bronze medallist Cheryl Murphy won an all-US affair against Skylar Lingl.

Cuba gained bronze in that division through Leon Cirelys Martinez, who beat Canada’s Melissa Bratic.

The second gold for United States came in the next final, when former world team bronze medallist Maya Wasowicz triumphed over Venezuela’s Omaira Molina.

Their third came when Torres defeated Diaz and the fourth was won by Thomas Scott in the men’s kumite under 75kg final.

He beat Jamaica’s Alton Brown to win gold, the bronze claimed by Argentina’s Jullio Ichiki.

Another noteworthy result came in the men’s under 60kg final, where Brazil’s Douglas Brose, considered perhaps the country’s greatest karateka of all time, beat Uruguay’s Maximiliano Larrosa to win his sixth Pan American title.

That result saw the 33-year-old regain the gold he had last won in 2017.

Team golds were won by Dominican Republic and Peru in the kata and Brazil and Venezuela in the kumite.

In the team kata finals, Dominican Republic saw off Peru in the men’s event, though the Peruvians gained women’s gold by beating Brazil.

Brazil bounced back from one team defeat to win men’s kumite gold against Mexico, while Venezuela won the women’s team kumite title with victory over Canada.