The Peter Moody-trained Thermal Current has been scratched from Saturday's Blue Diamond Stakes at Caulfield.
Thermal Current has a muscle strain, Racing Victoria reported.
The colt had been the most fancied of Moody's runners and was an $8 chance to win the $1 million race.
Moody will still have three starters in the Group One juvenile feature - Dissident, Kona Breeze and Quest For Peace.
The Blue Diamond field has now been reduced to 14 with trainer Mark Kavanagh withdrawing Casquets earlier in the week when she drew the outside gate.