Batting first, SA piled on 194 runs courtesy of a mature 47 to opener Bailey Capel, who cracked six fours and a maximum in his 57-ball innings.
Josh Pengelley chipped in with 32 coming in at No.8, while Connor Dudley and Lucas Froude (both 29) also contributed with the willow.
Victoria Metro captain Jono Merlo took four wickets and top-scored with 62 runs in reply but couldn’t lift his team over the line.
Rookie-listed Redback Lloyd Pope, who was last year’s Under 19 leading wicket-taker, took 2/33 and bowled two maidens, while Pengelley claimed three scalps from eight overs to hold Metro to 9/183.
South Australia take on Tasmania in round three of the tournament from 10:00am (local) on Thursday.
SA has won its first game in the national under-19 championship, Vic Metro reaching 9/183 in reply to our 194— SACA Competitions (@SACAComps) December 5, 2017
Josh Pengelley took 3️⃣ wickets, Lloyd Pope ⬇️ 2️⃣ pic.twitter.com/ZSf0YCc7ty