A goal from substitute Emelio Caligdog five minutes from the end gave the Philippines all three points and revived their hopes of making it to the semi-final after the opening day defeat to Thailand.
The first 45 minutes was lacking in creativity as chances were few and far between.
Vietnam started better and threatened to score in the first 15 minutes through Le Tan Tai and Le Cong Vinh but were let down by their poor finishing.
On 31 minutes, Pham Than Luong picked up a loose ball and almost tested Eduard Sacapano with a decent shot.
The Vietnamese continued to dominate most of the play without creating much trouble for the resolute Philippines defence, while the Filipinos relied on counter-attacks but could not do much with their approach.
The Azkals started getting into the game more after the interval and earned a free-kick five minutes into the second half. Philip Younghusband fired wide after Dennis Mengoy’s effort was cleared by Vietnam’s defence.
Then the breakthrough finally came with five minutes to go.
Caligdong broke free in the box and Angel Guirado picked him out with a brilliant lob. The midfielder took the ball down well and finished with aplomb to give the Azkals what eventually proved to be the winning goal.
Vietnam almost equalised straight after with Tan Tai’s fierce shot, but the ball hit the bar and bounced back into play.
With the win, the Philippines will move level on points with hosts Thailand, who can ensure qualification with a win over Myanmar now.
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