A home side missing several of their most-experienced players scored four tries to three on Saturday against the Storm, comprising personnel from reserve grade and feeder clubs.
Without their premiership-winning first-grade players - who beat Leeds 38-4 on Friday night in the World Club Challenge - Melbourne still put up a decent performance.
They opened the scoring with an exceptional team try finished by Sunshine Coast Falcons winger Matt Sopa-Lowler.
The Warriors responded through tries to centre Solomone Kata and winger David Fusitu'a to lead 10-4 at halftime. The second try set up by quick hands from Peta Hiku and Blake Ayshford.
Second-rower Ligi Sao's try, off a neat grubber from stand-in captain Mason Lino, pushed the hosts further clear.
Hooker Harry Grant and winger Ryan Papenhuyzen crossed late for Melbourne, either side of a Warriors try to Lewis Soosemea.
The match at Rotorua International Stadium gave coach Stephen Kearney a chance to field six new players. Hiku, Agnatius Paasi and Leivaha Pulu all started, while Anthony Gelling, Matiu Love-Henry and Rotorua product Hayze Perham were given time off an extended interchange bench.
The major Warriors' concern was a knee injury to Paasi in his first carry of the game. The former Gold Coast prop had strained a medial ligament and would need assessment, coach Stephen Kearney said.
Hiku, Paasi and Leivaha Pulu all started whileAnthony Gelling, Matiu Love-Henry and Rotorua Boys' High School product Hayze Perham were given time off an extended interchange bench.
The Warriors face Gold Coast in a second trial match next week on the Sunshine Coast before opening their NRL campaign on March 10 against South Sydney in Perth.