New Zealand Derby winner Puccini is on trial for Melbourne when he runs at Hastings, but it is still unclear if the target is the Caulfield Cup or Cox Plate.

Puccini heads into Saturday's Group One Livamol Classic (2040m) as the $2 favourite after easily winning the Merial Mile at Awapuni in September, and his trainer Peter McKay says he's progressed well since.

Puccini faces a useful field for the third leg of the Hastings weight-for-age series, but McKay doesn't think it's as strong as the second race in the series two weeks ago, won by Pure Champion from I Do and Soriano.

"He's going up to weight-for-age but the field's probably dropped away slightly from what it would have been if he lined up against the Group One horses last start," McKay told NZ Racing Desk.

"There's a few handy types in there but not completely what was in there two weeks ago. Hopefully he wins, but things can happen in the race."

Puccini would probably need to win at Hastings to show he could be competitive in Melbourne.

"He's nominated for the Caulfield Cup and the Cox Plate so we'll make a decision after Saturday where he goes, whether it's the Caulfield Cup or straight into the Cox Plate," McKay said.

"I'd like to see him do everything right on Saturday first."

Puccini was the dominant three-year-old in the last New Zealand summer, culminating in a victory over subsequent Australian Oaks winner Rising Romance in the New Zealand Derby.

He may have been over the top for the season by the time he went to Australia, where he finished 12th in the Rosehill Guineas after his saddle slipped and fifth in the Australian Derby.