The set weights conditions of the QTIS Plate at the Gold Coast have trainer John Zielke confident he can maintain his dominance of recent two-year-old racing in Queensland.

The Zielke-trained filly Spot the Diff is favourite for the Saturday's $100,000 race which is the showcase for the QTIS yearling sales later this month.

The Caloundra trainer has had a big season with juveniles, winning six races with four individual youngsters and collecting more than $250,000 in prize money and bonus payments.

Spot The Diff was a brilliant Sunshine Coast winner at her last start on February 19 having won a race at Doomben in October.

She is by leading sire Snitzel and Zielke believes she can measure up to better company in the winter.

"Saturday's race is a set weights plate so given Spot The Diff carried 58 kilograms to a convincing win last time she looks well in on 55," Zielke said.

Fellow trainer Kelly Schweida elected to scratch his well-bred colt Double Superaltive from Doomben on Wednesday to run in the QTIS Plate.

Double Superlative is by Turffontein out of the former top race mare Kidnapper making him a half brother to the Schweida-trained former top-liner, the injury-prone Cape Kidnappers.

"We didn't want to run him on a bog at Doomben on Wednesday. He hasn't trialled but we have put blinkers on him for the first time," Schweida said.

"Not much went right at his first start in October and we hope for better on Saturday."

At his first start at Doomben, Double Superlative showed a lot of pace but raced greenly and Schweida hopes the blinkers will make the gelding race more truly.