Duncan is hoping the Toowoomba Cup form will again stack up after Gold Coast stayer Honorable Spirit ran second in last year's Darling Downs feature before going on to victory in the 2021 Queensland Cup.
"I'm hoping it works out that way," Duncan said.
"My bloke is a 97-rater now after his Toowoomba Cup win and he's got a bit of weight with 59kgs to carry.
"His Toowoomba Cup win was very good and he will have no problem running out the extra trip over 2400 metres."
Sunshine Coast trainer Duncan wants a firm track for Seat Of Power, who is yet to win in seven starts at Eagle Farm.
"He's never won there but he's run second three times and weight cost him on those occasions," he said.
Since 2000, only four locally trained gallopers have won the Queensland Cup.
Honorable Spirit's win was the first for a Queensland-trained stayer since Spechenka's triumph for Beaudesert trainer Ben Ahrens in 2012.
Toowoomba's Ron Maund also won the Queensland Cup with Ice Chariot in 2007 while veteran Gold Coast trainer Harold Norman was successful with Kugelhopf in 2003.
The Queensland Cup has attracted a field of nine stayers including three interstate raiders.
Smith, who won the Queensland Cup two years ago with Grey Lion, gives Brown Thomas a strong hope.
"He's going good and he won at Doomben two months ago," Smith said.
Brown Thomas won over 2200 metres at Doomben in August and is coming off a last start fifth over 2400 metres at Rosehill on September 28.