Kawasumi Nahomi broke the deadlock with a long-range volley from outside the box. Vietnamese defence tried to clear Ogimi Yuki's corner on the left flank but it fell to Kawasumi's path and she drove home with one remaining minute in the first half.

Despite dominating the second half, the few hundred Japanese fans had to wait until the 65th minute to celebrate the second goal as Kiryu Nana was on hand to nod home the rebound resulting from Iwashimizu Azusa's first header hitting the crossbar.

Four minutes later, Ogimi Yuki fired a low shot past Dang Thi Kieu Trinh to extend the gap to three goals before Kawasumi made it 4-0 with a curl into the high corner of the goal to end any hopes of a comeback from the home team.

Japan are now in first place with four points after one draw and one win, while Viet Nam dropped to third place with three points out of one win and one loss.

The world champions face a much easier task in the last match, only meeting Jordan, who are already disqualified. Meanwhile, Viet Nam need magic to go through as their opponent will be defending champions Australia.

"As we expected, Viet Nam played defensively but much more defensively than we thought," Japan's coach, Sasaki Norio, said in the post-match press conference. "In the second half, we were able to take advantage of our strength and skills to score goals. This victory will give our players more motivation in the next games."

The Vietnamese team's coach Chen Yun Fa said, "It was an extremely difficult game for us against the world champions but I am happy with the players because they tried their best even though they conceded goals," Fa said.

In the previous match of Group A, Australia dominated Jordan in a one-sided game as captain Gill scored a double in the first half and substitute Katrina Gorry added one in the second to lead Australia to a 3-1 win, their first after drawing Japan in the opening game.

Australia will next play the home team Viet Nam in the last round of matches of Group A on Sunday and Stajcic expects a tough game from Viet Nam.

"They beat Jordan 3-1 in the opening, the same score as ours, so I expect it will be a tough match for us on Sunday," Stajcic said.

With two losses out of two games, Jordan became the first team to be eliminated from the tournament, but coach Okiyama Masahiko was pleased with the spirit his players displayed against the defending champions.

"We wanted to win this game and tried to play modern football and plotted a system to deal with Australia's power, but it did not work. I take the responsibility for the defeat," Jordan's coach, Okiyama Masahiko, said in the post-match press conference.

"After losing the opening game, it's more difficult to play the next game, especially against reigning champions Australia. But I'm happy with what players showed today. They showed that Jordan have something to show at the tournament," he added.

Today, in Group B's second round of matches, South Korea, who temporarily lead the group after a 12-0 rout of Myanmar in the opener, will take on Thailand while China, who are second with a 7-0 thrashing over Thailand in their first match, play against Myanmar.

VNS/VNN