New Zealand trainer Andrew Forsman expects the early stages of the Victoria Derby will be crucial to the chances of Long Jack winning the $2 million Classic at Flemington from the outside barrier.

Long Jack was pinpointed early by co-trainers Murray Baker and Forsman as their Victoria Derby candidate.

The colt confirmed plans for Saturday's 2500m staying feature for three-year-olds by winning last week's Listed Geelong Classic (2200m).

"He's always shown plenty of quality when he was a two-year-old in New Zealand in the autumn. He's bred to stay, particularly on the dam side so that gave us a lot of confidence to bring him over and have a crack," Forsman said.

"It's up to him whether he justified the faith we put in him and he put his hand up last time.

"It was good to see so the next logical thing is to have a crack at the Derby and hope he can run the trip out."

Long Jack is by champion So You Think, placed in the 2010 Melbourne Cup, out of Extravaganza, a mare by Monsun, the sire of three Cup winners Fiorente (2013), Protectionist (2014) and Almandin (2016).

The Geelong win was the colt's second from four starts in Victoria this campaign after he opened his account in a Ballarat maiden before unplaced runs over 1600m at Caulfield and 1800m at Flemington.

"He finally got a bit of luck in the run at Geelong which he has needed," Forsman said.

"He's not the strongest of three-year-olds and struggles to do work at both ends of a race which he probably has had to do in the couple of runs before that.

"We were really happy how it all panned out at Geelong and he showed the staying qualities we thought he had."

Long Jack jumped from barrier 13 of 16 at Geelong and will jump from the outside barrier in Saturday's Derby for which he is a $19 chance.

"In a lot of ways we just have to hope we get lucky again," Forsman said.

"It's going to have to be similar sort of tactics, just punch forward early and hope he can slot in somewhere midfield.

"He looked outstanding going into Geelong. He had really improved and he's further improved.

"What happens in the first four or five hundreds metres will tell the tale."

Forsman says Long Jack has given the indication he can run the 2500m.

"It's all about what sort of trip you get without doing too much work early on. But we're pretty confident he will hit the line," he said.

Before taking on Forsman as a partner, champion trainer Baker won the Victoria Derby in 2010 with Lion Tamer.