Zoustar couldn't figure in a Flemington jump-out on Friday but the valuable colt showed Chris Waller he is on target to make his Melbourne spring carnival debut.

The brilliant three-year-old followed home Thump, Happy Galaxy and Sidestep at the end of a four-horse 800m workout but the result didn't matter to Waller.

"That's pretty standard for our triallers," Waller said.

"You would be flat out finding a horse at our stable that's won a trial, so it's no different this morning.

"We just keep them happy, keep them on the bridle and race day they know when to switch on."

One of the most sought-after colts racing in Australia, Zoustar is in Melbourne to try to improve his Group One record in the Coolmore Stud Stakes at Flemington on Saturday week.

Zoustar is expected to start favourite to win the Coolmore after claiming the Group One Golden Rose and the Roman Consul Stakes at his two most recent Sydney outings.

"It was a nice workout and to my eye it looked a pretty competitive workout," Waller said.

"They are four pretty handy horses and we were just out there to give him (Zoustar) a look up the straight, not do too much."

Waller said Zoustar would have another solid workout on Tuesday morning to have him properly wound up for Derby day.