Melbourne Cup contender Jan Brueghel has been ruled out of the $8.5 million race, with connections stunned by Racing Victoria stewards’ decision to withdraw the Irish horse.

The unbeaten colt trained by Aidan O’Brien was among the top favourites in the early betting and had been “bouncing” in preparations at Werribee, according to Coolmore’s Tom Magnier.

Jan Brueghel completed light work on Tuesday morning just hours before his withdrawal was confirmed following mandatory scans three days earlier.

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“He went through all the protocols in Ireland before departing to come down here,” Magnier told SEN.

“The lads have been very happy with the horse, he’s been bouncing out there in quarantine (at Werribee).

“But the vets have come up with the decision that has been made that he doesn’t pass the veterinary inspection to run in the Melbourne Cup.

“Obviously I’m extremely disappointed for the staff, all our team that have put in so much work both at home, travelling him down and getting him here. I really feel for them because they were excited about this.

“But at the end of the day at Coolmore the horse comes first, everything about the horse. A decision has been made and that’s that.”

Magnier suggested his team had no injury concerns with the horse.

“The decision was Racing Victoria,” he said.

“We’re just very disappointed. Aidan will keep talking to the lads. I’m just very disappointed for all the staff.”

Racing Victoria confirmed stewards made the decision based on “specialist veterinary advice”.

“Reports received from an expert panel of internationally renowned equine surgeons and diagnostic imaging specialists, who reviewed Jan Brueghel’s CT scan results, indicate that the horse is currently at heightened risk of injury,” RV said.

“Following advice from RV Veterinary Services in relation to the specialist opinions from the independent imaging panel, RV Stewards ordered the withdrawal of Jan Brueghel from the Melbourne Cup on the basis that he was unsuitable to compete.”

The decision leaves 2014 Melbourne Cup-winning jockey Ryan Moore without a ride for the Flemington classic.