Former Sydney mare Doubt She's A lady has lived up to a recent unofficial trial to cause an upset at Doomben.

Doubt She's A Lady ($41) also continued jockey Ron Stewart's run of long-shot wins when she came from well back in the field to take out Wednesday's Class Three (1110m).

Trainer a Chris Munce admitted the win far from surprised him.

"She went like a bomb in a recent unofficial trial. She had heavy shoes on in the trial and I must admit I had something on her at big odds," Munce said.

"I don't know much about her background but she is well bred has thrived since she came up here."

Before she went to Munce, Doubt She's A Lady was trained at Hawkesbury by Scott Singleton who took over when David Vandyke moved to Queensland last year.

Stewart recently won on $61 chance Colour Charge and he is building up plenty of support from trainers since returning to race riding in December after a break.

Earlier, Munce predicted a bright future for Son Of A Brut ($1.50) who won the maiden (1350m).

"I have always thought he would make a very good 1600 to 2000 metre horse later in his career," Munce said.

Son Of A Brut is owned by an Adrenaline Thoroughbred syndicate which also races the Munce-trained stakeswining two-year-old Champ Elect.

Another relative newcomer to Queensland, former Victorian mare High Africaine, broke through for trainer Ben Currie in a 1600m-maiden.

"I bought her for only $5000 at a dispersal sale. We were a bit worried the 1600 metres might have been too short for her but she was too strong," Currie said.

"She is a city winner now and that will add plenty to her value as a broodmare making her a real bargain."