The Vietnamese under-19s kept up a relentless attack on a strong Malaysian defensive line, with good performances from midfielders captain Van Quyet and Hai Huy, and the two strikers Minh Tuan and Dinh Bao.
The home team applied constant pressure in the first half but failed to score. Vietnam carried on their aggressive play in the second half and took the lead four minutes after halftime after Dinh Bao headed home a free kick from left winger Quoc Phuong.
The Malaysians fought back in vain as Vietnam’s Van Quyet skirted Malaysian defenders from the left flank and beat goalkeeper Mohd Khairul.
“The players applied the strategies very well and this win makes our way to the semis easy,” coach Vo Hoang Buu said.
In other action, Thailand crushed Cambodia 3-0 and Australia drew 1-1 with Singapore.
Vietnam will play the second group stage match against Myanmar Thursday at Thong Nhat Stadium.