Epsom Derby winner Golden Horn, ridden by Frankie Dettori, denied French mare Treve an historic third Prix de l’Arc de Triomphe with victory at Longchamp.
Dettori, winning the race for the fourth time, pulled Golden Horn wide early in the race before slotting in behind the leader.
They were well positioned before moving clear of Flintshire and New Bay, who finished second and third respectively.
Treve finished fast but had to be content with fourth.
Golden Horn had already enjoyed a superb season with wins in the Derby, Dante Stakes and Coral-Eclipse – and bounced back from a shock defeat in the Juddmonte International to claim the Irish Champion Stakes.
The money earned for those victories meant the 120,000 euros (£88,600) owner Anthony Oppenheimer spent to add the John Gosden-trained horse to the field for the world’s richest turf race was a relatively small price to pay.
“I really believed in the horse,” said Dettori. “I was going so fast in the last 300 metres I knew no other horse would pass me.
The winning horse will head for stallion duties next season but could have one more run at the Breeders’ Cup in Keeneland, Kentucky at the end of the month.
“The owner is quite keen on the Breeders’ Cup. It gives us one day short of a month, he’s got a great constitution and he travels well,” said Gosden.
“If he’s in good order next week, there’s no reason why he can’t go there.
“I keep saying he’s a better horse coming from off the pace and he was today.”