Binocular will not defend his champion hurdle title at Cheltenham tomorrow (Tuesday) after connections withdrew the horse from the race at the final declaration stage, on advice from the British Horseracing Authority (BHA).

Binocular had been treated for an allergy two weeks ago, and subsequent testing revealed that the medication used to treat the condition was still in his system last weekend.

The BHA advised that this would have led to a positive test on the day of the race, when horses must be drug-free.

The horse’s trainer Nicky Henderson released a statement confirming that Binocular will not run.

“He had an allergy two weeks ago that did not respond to initial medication and, on veterinary advice and well within normal parameters, he required a further treatment the following day,” said Mr Henderson.

“As we were getting close to the most important day of the year, I thought it prudent to take a precautionary test which, surprisingly — let alone devastatingly — has also shown to be positive.”

The BHA confirmed that Mr Henderson had requested an elective test, and that repeated tests from Thursday to Saturday showed that levels of the medication were remaining constant.

“We advised Nicky Henderson and his vets of this result on Saturday night and the clear advice was that Binocular would test positive on race day,” said a spokesman.

The BHA clarified that because the substance is a legitimate medication and the horse has not run, this is not a breach of the rules.

Several bookmakers have offered refunds on ante-post bets placed on Binocular, who was priced at around 3-1 favourite to defend his crown.

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