Australia opened its campaign with a 5-1 win against Cambodia with Lleyton Brooks scoring a double and Kai Trewin, Dylan Ruiz-Diaz and Harry McCarthy also getting on the scoresheet.
Iannucci was an unused substitute in the match, but, the Cobram junior made his international debut in the second match against Vietnam in front of more than 4500 spectators at the Thong Nhat Stadium.
The Melbourne City youngster played off the left flank and was on the park as Australia pushed to a three-goal lead just before half-time.
The hosts pulled one back just before the break and Iannucci was subbed off at about the hour mark.
Australia rounded out the win with Sydney FC’s Marco Tilio scoring his third goal of the match in the 93rd minute.
Iannucci sat out Australia’s third match against Thailand, which ended finished 3-1, with Ruiz-Diaz, who has played two games for Central Coast Mariners in the A-League, scoring a brace.
The Young Socceroos take on Malaysia tonight at 6.30 pm (AEST) before playing Singapore on Thursday night.
With the top two in each group going through to Friday’s semi-finals, a win in either match will ensure Australia progresses.
In the knockout stage, the Young Socceroos are likely to face one of Indonesia or Myanmar.