Desert Crown won the Derby at Epsom by two and a half lengths
Derby winner Desert Crown has been ruled out of the King George VI and Queen Elizabeth Stakes on 23 July.
The Epsom victor had been due to race again with third-placed Westover, who went on to win the Irish Derby.
But trainer Sir Michael Stoute has said Desert Crown will not run after reported to be suffering a "foot niggle" on Wednesday.
"The colt won't be going to Ascot for the King George," Stoute told the PA news agency.
Bruce Raymond, racing manager to owner Saeed Suhail, said Desert Crown could not be risked, despite what he felt was a minor injury.
"If it were a lesser horse, we might take a chance, but you dare not take a chance with a horse like this," he said.
"You can't go to a race like this 95% fit.
"Only time will tell, but hopefully he'll be able to get him back - although Michael didn't say anything to me - I'm thinking about York [Juddmonte International] and then the Arc."
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