Binanti had been heavily fancied for victory at Ascot but struggled with the pace even before the midway point.

The race was won by Puma, the 13-8 second favourite, while Binanti finished some way behind 5-1 shot My Daisychain in third.

Patrick Chamings, who trains Binanti, suggested foul play in the wake of the result. His horse had previously won convincingly at Southwell and Goodwood.

After inspecting the horse, he told the Racing Post: "What I found was very strange, as his eyes were severely bloodshot, like I've never seen in a horse before.

"He was so badly distressed and blue for three-quarters of an hour, which is most unsusual.

"He'd been in such fantastic form at home but [jockey] Jimmy [Quinn] said he didn't feel like the same horse from halfway and he ran like a horse who'd been given something.

"I can tell you he's a machine of a horse and I'm flabbergasted about his run. In the paddock Jimmy said he would definitely win."

The horse was automatically dope tested by stewards at the course and the result of those tests will be revealed later this week.

And Chamings believes the results will prove the horse had been doped.

The Hampshire trainer insisted there was only a very small window in which the horse could have been tampered with.

He explained: "There was an opportunity for the horse to be 'got at' as I went for a bite to eat with the lass who led him up between 11am and 11.25am.

"I had him examined straight afterwards and I was told that he had an increased heart-rate, which was probably down to stress."

Chamings, though, is certain there is no other time the horse could have been "got at".

He concluded: "I'm certain nothing could have happened to the horse either at home, before he left, or on the way to Ascot as I was with him all the time and he was fine."

Quinn, meanwhile, refused to make any accusations.

He said: "I don't know what happened, but that obviously wasn't his form.

"Remember horses can go overnight at this time of year. He's had a busy time and just could have had enough."

Chamings' accusations ended a dismal 10 days for the Jockey Club.

The club's head of security Jeremy Phipps was sacked this week in the wake of Panorama's expose of corruption in racing.