High-class Perth three-year-old Disposition makes his eastern states debut at Flemington with his jockey Craig Williams convinced his West Australian form will hold up.

Disposition's owner Bob Peters sent him to Mornington trainer Wez Hunter to be prepared for the major three-year-old autumn races.

Saturday's CS Hayes Stakes (1400m) will be his lead-up to the Group One Australian Guineas two weeks later.

The winner of four of his six starts, the three-year-old son of Reset has not been seen since his close second to the Chris Waller-trained Moriarty in the weight-for-age Group One Kingston Town Stakes (1800m) at Ascot on December 6.

Williams made the trip to Balnarring a little over two weeks ago to partner the gelding in a jump-out.

"His form from Perth is excellent," Williams said.

"We get to understand how strong that form is after he ran second to Moriarty in Perth and we understand that form in weight-for-age races in the eastern states.

"I was delighted with the way he felt in his trial and he's trialled again since.

"I've watched his trial and he looks like he's progressing well."

Disposition will be tackling some of Melbourne's best three-year-olds including Stratum Star, Chivalry and the up-and-coming Lucky Liberty who is undefeated in three starts.

Disposition has drawn barrier four and with the rail in the true position Williams is certain the gate is an advantage.

"The track has been racing really well and the weather looks nice," Williams said.

"If the track plays really even then it's a lovely draw."

Disposition was a $5.50 chance on Friday behind $5 co-favourites Stratum Star and Lucky Liberty.