Coolmore's decision to purchase a stake in King's Legacy has delivered immediate success, the colt stamping himself one of the country's best two-year-olds with a second Group One win in the Champagne Stakes.

His narrow victory over game Victorian Glenfiddich has also given jockey Hugh Bowman a rare clean sweep of the juvenile triple crown after earlier wins in the Golden Slipper (1200m) on Farnan and Sires' Produce Stakes (1400m) on King's Legacy.

A $1.4 million yearling purchase for James Harron Bloodstock, King's Legacy has been on the radar of Coolmore's Tom Magnier for some time.

"Coolmore loved this colt and Tom Magnier was under-bidder," Harron said.

"It is incredible how it is has worked out with Coolmore buying into this colt between his two Group One wins.

"This campaign was all about the Sires' and the Champagne and it is great when a plan like this comes off."

Trainers Peter and Paul Snowden strategically targeted the second and third legs of the two-year-old triple crown with King's Legacy, adamant the colt would be at his best over the longer distances.

They were rapt to see the plan come to full fruition in Saturday's 1600-metre race.

"There was always a thought in our minds that these were the two races that would suit him. As it has turned out, we've got them right," Snowden said.

"I think it is only the start of what you'll probably see as a three-year-old. He is definitely going to be a horse that is going to train on and a horse with a lot of substance and a good bit of quality about him."

Snowden believes the sky is the limit for King's Legacy in the spring, pinpointing the colt's attitude and will to win as compelling attributes.

"He gets his head out and really flattens out," Snowden said.

"He has a really good racing style and turn of foot and that is going to take him a long way."

King's Legacy became the first horse since Guelph in 2013 to claim the Sires' Produce-Champagne Stakes double.

And while the juvenile triple crown is usually about the horses, it has belonged to Bowman this year.

Having claimed his first Golden Slipper last month, Bowman judged the Champagne perfectly to celebrate his fifth Group One win for the season and third this autumn.

King's Legacy will now be given a break and aimed towards more Group One targets in the spring, the Golden Rose and Caulfield Guineas chief among them.

By Redoute's Choice out of Breakfast In Bed, the youngster is closely related to top sire Not A Single Doubt and Magnier says Coolmore is thrilled to have acquired him..

"We are always trying to find these colts and we have landed on one here," Magnier said.

"He has always been a very good looking horse and is dual Group One winner at two. He is a very exciting colt going forward."

King's Legacy started a $2.70 favourite and nailed Glenfiddich ($31) by a half neck with Ole Kirk ($4.80) another 1-1/4 lengths away.