Melbourne Cup favourite Jan Brueghel is sensationally ruled out of the race after shock decision from vets

Top European star Jan Brueghel has been ruled out of next Tuesday's Melbourne Cup due to a decision by veterinarians that has left the horses' connections mystified and angry.

Irish trainer Aidan O'Brien's stallion was the Cup favourite before Via Sistina's barn-storming Cox Plate run last Saturday.

A Racing Victoria statement didn't specify an issue, but said the Irish four-year-old was 'at heightened risk of injury' after failing a CT scan.

'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,' Racing Victoria said in a statement.

Coolmore stud boss John Magnier said his unbeaten four-year-old's withdrawal from the race came as a shock.

'He went through all the protocols in Ireland before departing to come down here. The lads have been very happy with the horse, he's been bouncing out there in quarantine,' Magnier told SEN, stressing that the horse had not been injured since arriving in Australia three weeks ago.

'But the vets have come up with the decision that has been made ... the decision was Racing Victoria's.

'We're very disappointed.

Jan Brueghel (pictured with trackwork rider Dean Gallagher) will be a shock omission from next Tuesday's Melbourne Cup - and the four-year-old's owners and trainer are not happy

The Irish raider (pictured at trackwork in Werribee) had no injury concerns before failing a test administered by Racing Victoria, his connections say

'Obviously I'm extremely disappointed for the staff, all our team that have put in so much work both at home, travelling down and getting him here.

'It's gut-wrenching.'

All Melbourne Cup entrants must be tested before they are allowed to run, and Jan Brueghel reportedly cleared those hurdles before leaving Ireland.

O'Brien slammed the testing system last month, branding it 'ridiculous'.

'Very few horses pass the criteria, especially young horses,' he told Racing Post.

'It is very difficult for three-year-olds to get through because they are still growing and their bones are still maturing, so I wouldn't be sure about any of them getting in and being allowed to run.

'It's ridiculous, really.'

Race fans got more bad news on Tuesday as bookmakers put Cox Plate winner Via Sistina at longer odds, with some listing the word 'doubtful' next to her name.

The seven-year-old mare broke Winx's record for the Plate last Saturday and was shaping as a firm favourite with punters, but has now dropped off as trainer Chris Waller delays a decision on whether she'll contest the race that stops a nation.