Champion jockey Zac Purton has already claimed one world-class major with a Japanese partner this season in the Caulfield Cup and he is hoping to strike again on Longines Hong Kong Mile dark horse World Ace after helping him with his barrier manners on Friday.

Purton's success in an injury-abbreviated Japan stint this year bore fruit when he picked up Admire Rakti for Melbourne and he jumped at the offer of Yasutoshi Ikee-trained World Ace.

"We know how strong the Japanese form is, his trainer is one of the top men in Japan and World Ace did beat Glorious Days home in the Yasuda Kinen, when he was well respected in the betting considering the hot favourite was Just A Way," Purton said.

"And he was one of the favourites again when he ran midfield in the Mile Championship last start after wrecking his chance by playing up in the gates and missing the start.

"He's been missing it in his last few, that's why his form looks the way it does on paper, but if we can get that part right World Ace can be a player."

World Ace joined four other Japanese horses for barrier practice after cantering around on the turf at yesterday's track session.

"We wanted him to go in the gates and make sure he was comfortable in them and also get him comfortable with having a handler next to him because in Japan they don't let horses have the handlers up in the barriers," Purton said.

"He stood in there really nice and quiet but, obviously, it was a bit different this morning as he'd just finished working. On race day, he's probably going to be a bit fresher and more jazzed up but, in what he had to do, he was good and that's important for him."

A win would not be the first Hong Kong victory for the Ikee family, although it was his father, Yasuo, who prepared Stay Gold to win the 2001 Vase.