The tough decision to geld Fast `N' Rocking has reaped an immediate reward for his connections with the sprinter finishing strongly to win first-up at Caulfield.

Giving co-trainers David Hayes and Tom Dabernig an early winning double on Saturday, Fast `N' Rocking, backed from $7 to $5, defeated Anatina by a half neck in the Alannah Hill Plate (1100m).

Runner-up in the 2013 Group One Blue Diamond, Fast `N' Rocking notched his first victory since claiming the Group Three McNeil Stakes at Caulfield more than 12 months ago.

"As a colt he had his mind on other things," Dabernig said.

"It was a hard decision for the owners to make to geld him because he was a potential stallion prospect but then lost his way a bit.

"Hopefully now we've got a racehorse."

His victory came a race after three-year-old stablemate Firehouse Rock, another son of Fastnet Rock, boosted his Victoria Derby prospects with a narrow win over 1700m against his own age.

Firehouse Rock was having his third start after placings at Geelong and Bendigo and Hayes and jockey Nick Hall believe he has the makings of a Derby contender.