The major targets in an autumn campaign for Pierro are undecided, the glamour colt's owner says.

Greg Kolivos said all options - with the exception of an Australian Derby start - remained on the table for the Gai Waterhouse-trained star.

"We haven't locked in a specific program yet," Kolivos told Sky Sports radio.

"As you know, Gai doesn't lock in every single race in a campaign because the horse tells us a fair amount along the way.

"Most of his campaign will be in Sydney but we are not going to rule out the possibility of a start or two in Melbourne."

Pierro suffered his first defeat in an epic Caulfield Guineas but the result did nothing to harm his reputation as one of Australia's best gallopers.

He ended his spring with a Cox Plate placing and Kolivos said the $3.5 million earner was in the early stages of an autumn preparation.

"He's been back in Gai's stable for two-and-a-half, nearly three weeks now, just slowly building up," the owner said.

While Pierro confirmed his prowess over a middle distance in the Cox Plate, a similar route to 2000m in the autumn is unlikely.

"For him to head down that sort of path it takes him towards the (Australian) Derby and the likelihood of him running in the Derby is slim," Kolivos said.