Darren Weir got off the mark in his premiership defence as Backbone dismissed any concerns his trainer had leading into Saturday's staying race at Moonee Valley.

Weir won his first Melbourne premiership last season with 86 city wins and took three races to get on the board in 2014-2015 as six-year-old Backbone raced to victory in the Melbourne Signage Concepts Handicap (2500m).

Backbone won over 2000m at Flemington last start with 55.5kg but a rise in weight had Weir questioning whether the gelding could make it back-to-back city wins without engaging a claiming apprentice.

"He had trained on well since he won last start but my little concern was the 59 kilos today," Weir said.

"I was keen to claim on him but the owners wanted to stick with Ben (Melham). And they were right."

Backbone ($4.60) enjoyed the run of the race, with Melham positioning him in fifth position behind a trio up front who set a decent tempo.

He moved into the race strongly approaching the home turn and went on to win by 1-3/4 lengths over Zabeelionaire ($11) with another two lengths to Sacred Flyer ($9.50) in third.

Melham believes next year's Adelaide Cup could be a suitable long-range target for Backbone should connections decide to look that way.

"I think if he was to target a race like the Adelaide Cup he would be competitive," Melham said.