Damien Oliver is without a Melbourne Cup ride with Durston being ruled out following a CT scan.

Caulfield Cup winner Durston has been ruled out of the Melbourne Cup after a 'grey area' showed up in a CT scan taken on the stayer. 

As part of Racing Victoria's requirement for all Melbourne Cup contenders, Durston underwent a scan at Werribee last Friday. 

In a statement posted on social media, Chris Waller Racing posted there was a small lesion in Durston's left hind leg. 

"The specialists cannot determine whether it is old or new or whether it is even something to be concerned about, but we must respect this" the statement said. 

"It is about safety, for the horse and the rider and the longevity of the horses. 

"It is very disappointing for all connections of the horses as well as my stable because so much time and effort goes into into these horses. 

"It's just heartbreaking." 

Durston galloped at Flemington on Tuesday morning and Chris Waller Racing said the stable's vet trotted up the stayer and he was sound. 

"We must respect modern science and learn from this," the statement said. 

"The horse will undergo an MRI scan to investigate further." 

RV said members of the international imaging panel who reviewed Durston's CT scan were of the opinion the stayer was at a heightened risk of injury. 

The enforced veterinary requirements were introduced last year following the deaths of horses following injuries incurred in the Melbourne Cup, the most recent being Anthony Van Dyck in 2020. 

With the scratching of Durston, champion jockey Damien Oliver is now without a ride.