The Storm were a little sloppy early on with Nelson Asofa-Solomona giving away a penalty for a tip tackle on former Melbourne playmaker Blake Green.
While Asofa-Solomona escaped report, Manly's Addin Fonu-Blake was later put on for a high tackle that caught the jaw of Storm halfback Cooper Cronk.
Exciting Melbourne rookie Jahrome Hughes, who played fullback, with Cameron Munster reverting to five-eighth, opened the scoring for the home side thanks to a backhand pass from Smith.
The Sea Eagles hit back through winger Matt Wright after a long cut-out pass from fullback Tom Trbojevic, who was one of his team's best. But that was all the visitors had to smile about.
A Storm try in the 39th minute that saw the ball travel from side to side, and then Suliasi Vunivalu barrel across from dummy half, crushed the Sea Eagles spirits.
That try put the winger among some elite company to have scored 38 tries in his first two seasons, alongside South's Alex Johnston, ex-Balmain flyer Larry Corowa, and Dragons greats Reg Gasnier and Ron Roberts.
Shortly after halftime, hard-working second rower Joe Stimson ran on to a Smith ball and with the lead out to 18-6, Melbourne never looked back.
Tries from Kenny Bromwich, Will Chambers and Cooper Cronk blew out the score before Josh Addo-Carr capped the match with a 50m dash to the line right on fulltime.
• Wests Tigers effectively ended Gold Coast's season in last night's other NRL game, dominating the mistake-prone Titans in a 26-4 win at Cbus Super Stadium.
The result all but derails Gold Coast's top-eight aspirations, who before this round needed to win all six remaining games to have any chance of playing finals footy.