Tasmanian Derby winner Jerilderie Letter will be tested in Melbourne in a two-run winter campaign which will define his four-year-old season.

Jerilderie Letter's Tasmanian Derby win in February has taken on greater significance in recent months given he defeated the Darren Weir-trained Howard Be Thy Name.

Howard Be Thy Name won his next four starts, including the Group One South Australian Derby, and finished fourth in the Queensland Derby.

Tasmanian-based Jerilderie Letter will make his mainland debut at Caulfield on Saturday with trainer Adam Trinder planning to run him in the 1400m handicap for three-year-olds instead of a benchmark race against older horses.

His next two starts will determine whether connections stick to the plan to target Tasmanian summer carnival races or raise the bar and look at the Melbourne spring.

"I'm really interested to see what assessment we make of him after these two planned runs in Victoria as to where he fits in," Trinder said.

"I feel he's in really good order, and it will be interesting to see whether we raise the bar and look to October, November in Melbourne or keep to our original mindset of just playing in Tassie over the summer carnival."

Trinder said the rise of Howard Be Thy Name was a measuring stick for Jerilderie Letter.

"Coming off that Howard Be Thy Name form, you would be tempted to contemplate finding a race through the spring carnival, whether that be in the early or latter part of it," the trainer said.

"With all due respect to Jerilderie Letter, Howard Be Thy Name probably improved off his Tasmanian Derby placing and went from strength to strength.

"We're hoping our horse can take the next step as well."

While Jerilderie Letter won the Derby over 2200m, Trinder believes he is predominantly a 1600m horse.

Jerilderie Letter was beaten first-up at Devonport recently but Trinder was happy with his second in a 1350m-benchmark 82 and believes he's a stronger horse this campaign.

"He stepped away slowly and was forced to work for the entire race and was just found a bit vulnerable late," he said.

Apprentice Jake Bayliss has the ride at Caulfield.