Goldream and Martin Harley © Photo Healy Racing
Royal Ascot winner Goldream lunged late to land the Qatar Prix de l'Abbaye de Longchamp.
Robert Cowell's King's Stand hero, subsequently fifth in the Nunthorpe, encountered his favoured fast ground in Paris and was always moving powerfully in midfield.
Last year's runner-up Rangali committed for home in the final furlong, but Goldream weaved his way through under Martin Harley to get up and claim another Group One prize.
The William Haggas-trained Muthmir was third, with last year's winner Move In Time, trained by David O'Meara, not far behind.
Cowell said: "That's outstanding - absolutely brilliant. I know he's good, but to win two Group Ones in one year is pretty outstanding stuff.
"All year he's been working brilliantly and just looks a different horse altogether this year.
"We worked him about 12 days ago in Newmarket with a horse called Speed Hawk, who was beaten a neck in a Listed race at Ascot on Saturday, and he just absolutely hacked all over him.
"He'll go to Dubai now. He was going to go to the sales, but we didn't enter him and the owners decided to keep him.
" We brought him here for the trial but the weather wasn't right and he didn't run, but it's paid off. I'm looking forward to taking him to Dubai."
