Sun City is out of the Magic Millions Two-Year-Old Classic with a leg infection but could still be a chance to run in the Blue Diamond and Golden Slipper.

The Tony McEvoy-trained colt was a $9 chance in the $2 million Classic at the Gold Coast on January 12 after his win in the B J McLachlan Stakes on Saturday.

McEvoy said Sun City was in fine fettle on Monday and Tuesday but had a badly swollen ankle on Wednesday morning.

"We sent him to the hospital for tests," McEvoy said.

"We had three opinions from a surgeon and two vets that Sun City needed to go on the table immediately and have the infection flushed out.

"It didn't leave us enough time to treat him so he is out of the Millions. It is gut-wrenching but there is still some hope he could make the Blue Diamond or Golden Slipper.

"But that is something we will know further down the track. The main thing he is given every chance to recover."