Tony McEvoy hasn't shut the door on the Australian Guineas for Alpine Eagle after the colt powered home late to win the Autumn Classic at Caulfield.

McEvoy will monitor the colt before making a decision whether to back him up in next Saturday's Group One over 1600m at Flemington.

But he said a freshen up before heading to the South Australian Derby was the favoured option for a horse which was a work in progress.

"If the horse bounces out of this, he is still in next Saturday," McEvoy said.

"I just need to let the horse do the talking.

"If he gets home and he's not his 100 per cent normal self in the next 48 hours, he'll be straight back to Adelaide."

Alpine Eagle was sent out $1.95 favourite after a dominant last-start Adelaide win, yet on the turn his chances looked forlorn.

Firehouse Rock powered to the front but he was tired inside the final 100m as Alpine Eagle balanced up and made his charge.

Alpine Eage got there in time to defeat Minnesinger, which made his run closer to the inside, by a short half-head while Firehouse Rock was three quarters of a length away.

Jockey Damien Oliver said Alpine Eagle was still raw but possessed huge potential.

McEvoy found it hard to contain his excitement.

"He looked in a lot of trouble wobbling around here. For him to pick it up and win was incredible," McEvoy said.