New Zealand gelding Catalyst has been ruled out of the $5 million All-Star Mile with bruised fetlocks.
Trainer Clayton Chipperfield sent him to the Ballarat Vet Clinic on Tuesday fearing he was not quite himself after his below-par run in the Australian Guineas.
He told Racing Victoria stewards late in the day tests revealed Catalyst had bruising to his four fetlocks and he was officially withdrawn from Saturday week's All-Star Mile at Caulfield.
This season's Group One NZ 2000 Guineas winner finished a close second to Alligator Blood in a thrilling Group Three C S Hayes Stakes at Flemington last month in his Australian debut before disappointing when sixth in Saturday's Group One Australian Guineas.
Catalyst finished sixth in the public vote, with the top 10 in the poll offered spots in the All-Star Mile while the 15-horse field also includes wild cards.
With Catalyst's withdrawal, his place in the race will be taken by a provisional emergency, yet to be announced.
Alligator Blood dominates the All-Star Mile market at $2.80 with New Zealand mare Melody Belle second favourite at $6.