Harbinger is now 6/4 favourite for the Prix De l’Arc De Triomphe after his stunning display in the King Geroge VI and Queen Elizabeth Stakes on Saturday.

It was the first time the colt had raced in Group One company but he impressed in the Ascot showpiece by breaking the course record to storm to victory by 11 lengths.

Favourite Workforce was subdued, finishing second from last, while Irish Derby hero Cape Blanco was also left trailing in Harbinger’s wake.

Harry Herbert, racing manager to owners Highclere Thoroughbred Racing, has admitted that everyone involved is finding the success difficult to take in, saying: “I don’t think it’s really sunk in for any of us and it was one of those rare racecourse performances where it is difficult to believe it actually happened.

“I think it was a once-in-a-lifetime performance and it’s hard to understand how horses can improve so rapidly, but he obviously has done and is doing so.”

Herbert also said that he is now focused on securing success at the Prix de l’Arc de Triomphe at Longchamp in October.

He continued: “It was a great performance and a great training performance and we will almost certainly look towards the Arc now.”

Workforce has slumped to 10/1 for the Prix de l’Arc de Triomphe due to his poor performance in the King George, whilst Cape Blanco is 14/1.