Gai Waterhouse and Adrian Bott have continued their dominance of Sydney's pre-Christmas two-year-old races, producing Magic Millions prospect Storm Boy for a comprehensive debut win at Rosehill.

Starting a $1.85 favourite, the colt lived up to his barrier trial form, showing natural speed to lead then finding another gear when asked for an effort in the straight to score by 2-1/4 lengths over Traffic Warden ($5) with Canara ($3.80) another four lengths off in third.

Storm Boy's appearance in Saturday's Kia Ora Prague Handicap (1100m) came almost three weeks after his most recent trial and Bott said that was a deliberate move with the Magic Millions Classic in January front of mind.

"We scratched him from a midweek maiden, purely because we thought it was a bit of a rush getting him there off the back of a trial," Bott said.

"We wanted to give him the correct time to get to the races here and felt if he was going to be that Magic Millions prospect, the timing of the program of running today worked out much better.

"We will give him one more run. 'Magics' is still a while off, so it will probably be at the end of the month here in Sydney, or we could potentially look at Brisbane, you've got the Bruce McLachlan (Stakes) up there."

Waterhouse and Bott have now won four of the five Saturday juvenile races in Sydney this season and finished second in the other with Celestial Bling runner-up in the Gimcrack Stakes.

Their haul has included the trifecta in the Breeders' Plate and snaring the Golden Gift with unbeaten youngster Shangri La Express.

Tim Clark partnered Storm Boy and described him as a strong colt who took everything in his stride.

"He has probably nearly done a bit too well between trials so it's a good sign when a horse is thriving like that," Clark said.

"He's got a great attitude and I'm looking forward to the future with him."