Stable favourite Bergerac ($31) beat Honey Toast ($20) by 1-1/2 lengths with a short neck to Bluebrook ($10) in third.
The Toowoomba trainer said he had made it very clear before the race there was not much between his three runners and luck would play a major role.
“That is how it turned out with barrier one the big difference for Bergerac,” he said.
“There hasn't been much between the three of them throughout their careers but Bergerac is a stable favourite.
“He is really a big track horse so winning here today is a real boost.”
Bergerac will now be set for the Sunshine Coast Cup (1400m) on January 26.
Tregea continued his successful association with jockey Michael Murphy, who rode his first stakes winner on Bergerac on Saturday.
“Michael is very under-rated and we use him when we can,” he said.
Murphy said he had a lovely run just off the pace and got into the clear at the right time while jockey Jeff Lloyd felt Honey Toast would strip fitter for the run.