The Thunderbolts offered great resistance to the ladder leading U20 Penrith Panthers, before falling 28-14 at AAMI Park on Friday evening.
The home side opened the scoring through Junior Kiwi Tony Tumusa, who crossed in the corner to give the Thunderbolts the lead early.
The lead was short lived however as the visitors hit back with consecutive tries through debutant Jarome Laui and Dylan Fuad.
A lively second half was kicked off by John Filipo, who brought the Thunderbolts within reaching distance with an early try.
Mack Mason converted his first attempt on goal and the Thunderbolts trailed 12-10.
The Thunderbolts try kicked the U20 Panthers into gear, who responded quickly with back-to-back majors from Tyrone May and Nathan Cleary, which extended the away sides lead to 24-10.
A try from Josh Minhinnick narrowed the margin to 10 points for the Thunderbolts, but a further try from Christian Crichton sealed the win for an impressive U20 Panthers outfit.
Melbourne Storm 14
Tries: Tony Tumusa, John Filipo, Josh Minhinnick
Goals: Mack Mason 1
Penrith Panthers 28
Tries: Jarome Laui, Dylan Fuad, Tyrone May, Nathan Cleary, Christian Crichton
Goals: Nathan Cleary 4