Vietnam jumped to top of Group D after two wins, and were tied on six points with second-placed Myanmar but with a better goal difference.
Coach Mai Duc Chung gave a chance to his young players as he filled the field with five new names compared with the first match two days ago.
But they had no difficulty against the underdog rivals who could not make a single on-target shootout in the first 45 minutes. The Vietnamese side on the other hand scored a goal every 11 minutes on average and closed the first half 4-0.
Midfielder Tuyet Dung needed only eight minutes to open the score with a close-range finish.
Dung and her teammates wasted a dozen of chance before they added the second one from a penalty by Vietnam Player of 2016 Huynh Như. Two other goals went to Vu Thi Nhung and Tran Thi Thuy Trang.
The second half was no better for the visitors.
While Singapore goalie Noor Kusumawati Mohammad Rosman worked very hard to save her goal, Vietnamese keeper Tran Thi Kim Thanh had almost no chance to touch the ball.
Nhu added two more goals to complete her hat-trick, the second one for Vietnam in two matches. Nguyen Thi Bich Thuy scored one before substitute Nguyen Thi Nguyet finalised the final score of the game.
“I don’t want to talk about the result because Vietnam have been always considered a stronger team. But Singapore showed their better skills compared with what they performed in our tournaments previously,” said Chung, and added that he was satisfied with the win and Vietnamese players were safe and strong for the next matches.
On the other side, coach Caying Chen of Singapore said Vietnam were in a higher level. They showed a rapid and advanced playing style that Singapore failed to catch up with.
She said her players were not professional players so they had to work hard to resist the challenge from Việt Nam. However, it was a good chance for them to play better in the future.
In the next round on April 9, Vietnam will play Iran who are at third place with three points. Singapore, standing at fourth, will meet Myanmar who beat Syria 14-0 on April 6.-VNA