Tony McEvoy admits starting A Thousand Degrees in the Vain Stakes on debut is an aggressive placement but he would not be doing so unless he believed the colt had the talent to measure up.

A Thousand Degrees is one of two runners for the trainer in Saturday's Group Three race for three-year-old colts and geldings at Caulfield, joining stakes-winner Aspect.

"It's a bit of a task for him but we'll see what he can do," McEvoy said.

"He has trialled with stakes-class horses and trialled really well."

McEvoy says the chances of A Thousand Degrees rest on how the colt handles handles the occasion.

"I don't run my horses unless I think they've got a winning chance," he said.

"It's a very aggressive placement. The trouble with running young horses like this is if he makes a mistake he can't be competitive.

"If I ran him in a maiden and he made a mistake he could still be competitive, so that's the risk I'm taking."

A Thousand Degrees has shown talent in recent Flemington jump-outs and McEvoy will use a cross-over nose band, ear muffs, lugging bit and tongue tie on the inexperienced colt.

"He's a pretty aggressive horse," McEvoy said.

"They are all tools of the trade that we use. We've tried him in lots of gear and I feel this is the right gear for him to hopefully keep him a bit more composed."

Aspect won the Maribyrnong Plate on debut last spring.

His best result in four autumn starts was a second in the Group Two VRC Sires' Produce Stakes over 1400m.

"He's come back as a gelding and I'm very happy with him," McEvoy said.

Aspect finished sixth in a strong Cranbourne trial last week on unsuitable heavy ground and while McEvoy said the gelding might find 1100 metres too sharp, he said it was a good race to kick off in.

"It's a very hard race but I expect them to be competitive," he said.