Veteran jockey Jim Cassidy insists Zoustar is getting a physical presence to match his racing record as the colt prepares for a racetrack return in the Canterbury Stakes.

Cassidy says Zoustar, one of Australian racing's most valuable horses, promises to be a standout in the yard in preparation for his first start against older horses in the Group One weight-for-age sprint at Randwick.

"I'm sure you are going to see a magnificent horse parade on Saturday," Cassidy said.

"He is starting to turn from a boy into a man.

"He is starting to develop all over from his shoulder through to his hindquarters."

Zoustar steps out for the first time since he gave Cassidy his 100th Group One win in the Coolmore Stud Stakes, the colt's sixth victory in eight career starts.

He was given two barrier trials last month and Cassidy said there was nothing more trainer Chris Waller could do without giving the colt a start.

"The horse's attitude is at a level where he needs to go to the races," Cassidy said.

Cassidy rode another high-profile colt, the since-retired Pierro, to win the 2013 Canterbury Stakes, its first running as a Group One race.

Its elevation to the top bracket of Australian races has been confirmed with Zoustar one of six Group One winners in a field of 10 chasing a $400,000 purse.

But it is a horse yet to win at the elite level which price assessors think can beat Zoustar or at least supply a quinella for the three-year-olds.

Not Listenin'tome is the second favourite after winning first-up at Caulfield last month.

He ended his first campaign in the spring by chasing Zoustar home in the Coolmore Stud Stakes but he gives the impression he might have closed the gap on his rival.