On his home turf at Perth's ground, Smith starred in Western Australia's 18.13 (121) to 5.9 (39) win, collecting 25 touches as one of the most influential players.
The 177cm Smith – identified as a talent to watch for next year's NAB AFL Draft – patrolled the backline but didn't stop there and often ran the ball out of defence to set up teammates with composed disposal.
After a competitive first term, Western Australia was able to break away by half-time and booted 11 goals to four after the main break.
AIS-AFL Academy member Dom Sheed followed his best-on-ground effort in round one with another irrepressible performance.
Sheed is strong, hunts the ball, doesn't fumble and has a booming left-foot kick, all ingredients of a top-end draft pick come November.
He picked up a game-high 34 disposals and dominated the stoppages, the WA captain continuing his strong lead-in to next week's division one meeting with the highly-fancied Vic Metro side.
Jonathon Marsh was another highlight for the winners. The 190cm dangerous forward kicked four goals from 22 disposals, and proved he has some exciting traits.
Northern Territory had few winners, forcing coach Brenton Toy to try some players in different roles throughout the second half,
Midfielder Brayden McLean tried hard with 17 disposals – equal with teammate Jake Ferrell as the highest possession-winner for the Territorians.
Peter Chisolm-Espie, of Southern Districts, had 15 disposals and seven marks.
Vic Metro will play Western Australia at Patersons Stadium on Saturday to start the third round of the NAB AFL Under-18 Championships, while Northern Territory will head to Blacktown International Sports Park to take on NSW/ACT.
WESTERN AUSTRALIA 3.1 7.7 9.10 18.13 (121)
NORTHERN TERRITORY 1.4 1.8 4.9 5.9 (39)
GOALS
Western Australia: Marsh 4, Johnson 3, McCarthy 2, Sokol 2, Anderson, Bourne, Cameron, Edwards, Lim, Pickett, Sheed
Northern Territory: Ankers, Cox, Musgrove, W.Rioli, Roberts
BEST
Western Australia: Smith, Chatley, Walsh, Sheed, Main
Northern Territory: Chisholm-Espie, Gordon, Ankers, Farrell, Long, Roberts
Follow AFL website reporter Callum Twomey on Twitter at @AFL_CalTwomey.
