Melbourne jockey Nick Hall is leaving nothing to chance to help deliver a Japanese victory in the $1 million George Ryder Stakes at Rosehill on Saturday.

Hall will ride World Ace, a highly regarded six-year-old rated a genuine chance to beat a star-studded weight-for-age line up at his Australian debut.

World Ace has a reputation for being sluggish out of the gates and it was enough for Hall to make a special visit to Canterbury to put the horse through some barrier practice on Thursday morning.

"The horse can be a bit slow away so we just wanted to do some quiet barrier work with him," Hall said.

World Ace was on his best behaviour during the practice session but Hall is still wary and he wants to get some inside mail from Hong Kong's champion jockey Zac Purton about the horse's behaviour at the races.

"If he had done something wrong today I'd probably know what I'm in for," Hall said.

"But he's probably quite a clever horse and he knows it was only practice.

"He hasn't put a foot wrong with me and that's some concern and I just want to confirm with Zac that he will be like that on race day."

Purton rode World Ace when the entire ran fourth to the incomparable Able Friend in the Hong Kong Mile at Sha Tin in December.

One of four Japanese gallopers in Sydney for the autumn carnival, World Ace hasn't raced since Hong Kong but Hall has no doubt he will be riding a superior racehorse in a George Ryder Stakes that has three horses vying for favouritism.

"All the Japanese horses here are top quality horses and being colts they look fantastic," Hall said.

World Ace has a Group One Japanese 2000 Guineas placing to his credit and he is a Group Two winner of the Yomiuri Milers Cup at Kyoto last year.

At $7.50, he is assessed as the best of the two Japanese horses lining up in the George Ryder with Real Impact an $11 chance.

Shooting To Win firmed to outright $4.80 favouritism on Thursday, just ahead of fellow three-year-old Kermadec and Canterbury Stakes winner Cosmic Endeavour who are both at $5.