Green Moon is a happier horse than in the autumn and his jockey Brett Prebble won't be surprised if the reigning Melbourne Cup winner strikes early in his spring campaign.

Prebble has ridden Green Moon in two impressive exhibition gallops at the past two Saturday race meetings in Melbourne to ready the horse for his spring return.

"It wouldn't surprise me to see him performing well over a mile or 2000 (metres) which we've seen before he can do," Prebble said after Green Moon galloped at Caulfield on Saturday.

"He pulls up and he's quite clean in the wind, so he's not far off his target."

Green Moon resumed in the Memsie Stakes (1400m) last spring which is one of the possible kick-off points this year with the Makybe Diva Stakes (1600m) a week later on September 7 at Flemington also an option.

Prebble won the 2012 Melbourne Cup (3200m) on Green Moon while in the autumn this year he rode him to fourth placings in the Futurity Stakes (1400m) and Australian Cup (2000m).

The jockey has delayed his return to Hong Kong racing until after the spring carnival in order to ride for owner Lloyd Williams.

"In autumn he was quite naughty and was doing a bit wrong. He was really bully," Prebble said.

"He seems to be a much happier horse now and he's programmed better so from that point of view I do like to see that for a horse.

"At the moment, after his last two gallops if you were a trainer or jockey you would be walking away from the track pretty happy."

Green Moon sat off stablemates Thought Worthy and Seville in Saturday's hit-out, described by Prebble as "a proper gallop".

Thought Worthy was given a searching hit-out in front from the 800m mark but Green Moon was able to sprint past late to win in good style.

"He (Thought Worthy) had us both (Seville and Green Moon) off the bridle before the home turn and then I just waved the whip at him and he just put them away very quickly," Prebble said.

"It was a very good turn of foot and on the line he was enjoying his work. He's come back a really fit horse and a healthy horse."

Prebble was also pleased with highly-rated import Sea Moon who had a good look around up the straight in his exhibition gallop at Caulfield.

"He'll improve from the gallop and from having the look around, for sure," he said.