Robert Heathcote and Chris Anderson have each trained winners for the Think Big Stud but they posted their first victory with the famous colours as a partnership at Doomben.

Heathcote had a perfect home coming after a overseas holiday when Sugar Zone ($2.80) beat his stablemate Duchess of Rose ($10) by three-quarters of a length.

It got even better when the partnership also produced the quinella in the following race with Char Char ($3) and Vaulting Ambition ($15).

Anderson and Heathcote began their training partnership on May 1 and the double gave them their 35th winner.

Anderson said he and Heathcote had a lot reasons to thank Think Big Stud which had been great supporters when they were individual trainers.

The stud continues to race horses in the black and white check colours of the late racing world doyen Dato Tan Chin Nam.

"Sugar Zone is a home bred at the stud and he is one of several younger horses I got from them last year," Anderson said.

"He has done a good job in his first campaign and we might let him mature more for next year."

Anderson was also thrilled with the win of Char Char who led all the way.

"He has been so honest if any horse deserved a win it was him, " Anderson said.

Another new partnership, the Gold Coast's Toby and Trent Edmonds got their eighth win in two weeks of operation when Great Keppel ($5.50) broke his maiden after five previous seconds.

"He has been a real work in progress and an example of changing things," Trent Edmondson said.

"We have been jumping him to keep him sharp and we changed his gear with a nose roll and tongue tie. And we decided to ride him back in field so all in all the changes have helped."

Last season's leading apprentice Baylee Nothdurft won on Great Keppel but had to settle for a dead-heat on Justify ($5.50) who was joined on the line by Frangipani Moon ($15) in a thrilling finish.

A Brisbane Racing Club official said about 15,000 people crammed Doomben as part of the annual Mekka Day aimed at young racegoers.