Almanzor, last season's champion three-year-old, has been retired to stud after his disappointing run at Deauville last week.
The Wootton Bassett colt, trained by in France by Jean-Claude Rouget, carried all before him last year with victories in the French Derby, the Irish Champion Stakes and the Champion Stakes at Ascot.
Almanzor stayed in training as a four-year-old with a view to running in the Prix de l'Arc de Triomphe at Chantilly in October.
But he did not return to action until last Tuesday, when a disappointing fifth in a Group Three at Deauville, and time has now been called on a glittering career.
Sylvain Vidal, racing manager for part-owner Gerard Augustin-Normand, said: "I spoke with all the team, and we have taken the decision to retire the horse.
"It was not an easy decision to take, but everyone was in 100 per cent agreement that it was the right thing to do.
"The plan was to go to the Arc, but after his performance last week we could not have gone there expecting to win.
"He was a very good horse and was the best three-year-old in Europe.
"He has done everything he needs to do on a racecourse."
Almanzor won eight times from 11 career starts and earned over £2.1million in prize-money.
Vidal said that stud details for Almanzor will be announced "in a few weeks, after we have spoken to all the partners".
