Rough stablemate nabs short-priced juvenile in opening race knockout result.

On breeding, Autumn Boy could be in for a fruitful career if the turn-of-foot shown at Canterbury on debut is any indication.

A stable quinella in the Drinkwise Plate (1250m) got Chris Waller's stable off in a positive fashion in Sydney for King's Birthday Holiday racing but while $1.4 million colt Central Coast ridden by James Mcdonald was heavily backed into $1.65 favouritism, it was $51 chance Autumn Boy who quickened when asked by Jason Collett to knock over the hot fancy by a short-neck margin .

"He's always been a dream to deal with in terms of his work at home," stable representative Charlie Duckworth said.

"He is very passive and flies under the radar a bit and has never had a smack on the bum before.

"That was a really good reason for him to really accelerate and hit the line."

A $200,000 buy by Chris Waller and bloodstock expert Guy Mulcaster at the 2024 Magic Millions Yearling Sale, the son of five-time Group 1 winner The Autumn Sun impressed Collett who believes there is more to come over longer trips.

"He was one of the nicer types that I'd seen at the trials," Collett said.

"He improved again from the trials which was a good sign."

The Autumn Sun notched his successes at the highest level over distances from 1400-metres to 2000-metres, including the Group 1 Caulfield Guineas (1600m) and the Group 1 Rosehill Guineas (2000m).

On the dam side, Autumn Boy was the second winner for New Zealand-bred mare Rosegarden whose sire Savabeel also did his best work on the track well beyond a mile.

In the two-year-old event for fillies over the same distance, the Bjorn Baker-trained Pillow Fight ($8) won on debut.

By star sire Zoustar, Baker's racing manager Luke Hilton believes there is also more to over longer distances from their $375,000 purchase at the same sale as Autumn Boy was sourced last year.