The wait was worth it for trainer Kelly Schweida after powerfully-built mare Kentucky Woman scored a stunning debut win at Doomben on Wednesday.

Standing well over 16 hands high with an impressive physique, Kentucky Woman, the $3.60 favourite, unleashed an impressive final 400m sprint to win the Darley Australia Handicap (1110m) eased down by 3-3/4 lengths.

Schweida has played a waiting game with Kentucky Woman, giving the mare plenty of time to fill her ample frame.

"She's always shown us something but she was too out of proportion to race as a two-year-old," Schweida said.

"We educated her, gave her a couple of jump outs, and she went okay but she was always immature."

The mare's win was tinged with sadness for owner Lynn Legg, whose husband Norm died before he was able to see the four-year-old race.

"Norm always said from day one that this mare would turn out to be the best horse he raced and I'm sure today's win will mean a lot to Lynn," Schweida said.

Trainer Matthew Dunn has also had to be patient with Rock Academy, a five-year-old son of Fastnet Rock who took out the Sky Racing Handicap (1200m) at only his fifth start.

The gelding won his first race at Doomben in May last year when he defeated subsequent stakes winner Someday, before niggling injuries kept him on the sidelines for more than a year.

"He had hoof problems, nothing serious, but I've just kept him away from the hard tracks and taken him to the beach which seems to have done the trick," Dunn said.

"It was a good win today because they walked in front and he was still able to come from last to win."

Jockey Michael Cahill was impressed by Rock Academy's performance and believes he can measure up to better company.

"He went from going okay to having them beaten in a stride and I was pretty soft on him in the end," Cahill said.

Dunn and Cahill also combined to win the Landfill Logistics Plate (1200m) with Splendora ($6).

Wednesday's double was Dunn's ninth winner from his past 13 starters and took him to the lead in the Brisbane trainers' premiership, one clear of Robert Heathcote.