A Sydney benchmark race is firming as the most likely of three options trainer Bryce Heys has in mind for promising three-year-old Spieth.

An untapped sprinter, Spieth is nominated for three races on Saturday, including the BRC Sprint and the Fred Best Classic at Doomben.

The Doomben 10,000 and Stradbroke Handicap entry is among 14 nominations for the BRC Sprint and is assured of a run in the 1350m race.

But Heys has already ruled out a start against older horses at Group Three level.

Spieth is well down in the order of entry for the Fred Best Classic but he is guaranteed a start in an 1100m race for three-year-olds at Rosehill.

"At this stage I'll probably just accept in the Fred Best Classic and here in Sydney," Heys said.

"Going on the ballot for the Fred Best he's probably going to be an emergency and if that's the case he'll probably run at Rosehill.

"But we'll see what that brings tomorrow morning."

Spieth has been sparingly raced, having had three starts during a Victorian spring campaign and just two more in Sydney since coming back into work.

The colt didn't disgrace himself first-up in the Arrowfield Stakes during The Championships and then he made a one-act affair of a restricted-class race on the provincial circuit.

Spieth had five lengths to spare over his nearest rival at Kembla Grange but Heys said the nature of the win didn't reveal anything he didn't already know about the horse.

"I don't know that we necessarily learnt anything but it was more about the horse having a day out and getting things right," Heys said.

"He couldn't have been any more impression, however I don't know that it told us much about whether he is good enough to step up in grade."

Sam Clipperton takes the ride on Spieth with the horse's Kembla Grange rider, the in-form apprentice Rory Hutchings, honouring a prior booking.