Trainer Ciaron Maher is heading to the Caulfield Guineas with a colt he says is in the zone after Bon Aurum pressed his claims for the Group One race in the Prelude at Caulfield.

Bon Aurum ($9) settled off the speed with cover for jockey Kerrin McEvoy in Saturday's Group Three Caulfield Guineas Prelude (1400m) before making his winning run down the centre of the track.

New Zealand Group One winner Dal Cielo ($19) gave a great sight in his first Australian start but was overhauled late as Bon Aurum got home by a half neck over the fast-finishing Tulsa ($10).

Dal Cielo was a half head away third.

Race favourite Ready For Victory finished ninth.

Bon Aurum is the $8.50 fourth favourite in Caulfield Guineas with Press Statement a clear-cut favourite after winning Saturday's Stan Fox Stakes in Sydney.

Bon Aurum landed his first stakes win when he defied a wide run in the Listed race at Flemington last start.

Maher said Bon Aurum had always shown ability and had continued to improve his race craft as he has gained more experience.

"Credit to the horse, he's in his first racing preparation and he's just a really tough colt and really fit," Maher said.

McEvoy has won two Caulfield Guineas with Helmet and Long John. And while he says Bon Aurum isn't as classy, colt is on an upward curve.

Damien Oliver said Ready For Victory was didn't want to go early and was under pressure the whole way, before finishing ninth.

Opie Bosson is convinced Dal Cielo will take improvement out of Saturday's race, while Tulsa's jockey Ben Melham said the gelding wanted to lay in when making his charge.

"I think if he raced truly up the straight he wins comfortably," he said.