Kingdoms laid the foundations for a Group One mission during the spring carnival with an impressive first-up win in the Mercedes Benz Mile at Eagle Farm on Saturday.

Trainer Brian Smith will aim Kingdoms ($21) at the Newcastle Cup and Group One Metropolitan after he defeated Hi Son ($21) by 1-1/4 lengths with Belle De Coeur ($6) a short head away third.

Kingdoms was sent to Smith by owner Michael O'Keeffe after the four-year-old's previous trainer John O'Shea switched to head the powerful Darley operation.

"I'd won races with Southerly and Cruz By and Michael said he would send me one that I could travel interstate with for the big races," Smith said.

"I love light-framed stayers and this horse was very cruisy in the enclosure before the race and trainers know when they're like that they're ready to do the job."

Jockey Larry Cassidy paid tribute to Smith and his staff for coaxing the best out of Kingdoms who arrived from Sydney with an unenviable reputation.

"A couple of the Sydney jockeys said to me 'good luck with him' because he's got a bad habit of hanging," Cassidy said.

"I rode him in a trial and he drew barrier one which was perfect for him because he had the rail to follow but the draw was no help to him today.

"Even though he was a bit wide I was able to get him onto his right leg and he kept a pretty straight line all the way to the finish."

Smith said Kingdoms would have his next start in the Tatt's Mile (1600m) at Doomben.