Australia kept their hopes alive as Vietnam's were extinguished in the second Group D matches at the AFC Under-23 Championship in Doha.
After the Olyroos defeated Vietnam 2-0, United Arab Emirates and Jordan drew 0-0 on Sunday night to put the West Asian nations in pole position to advance to the knockout stages.
Jordan and UAE are top of the group on four points followed by Australia on three, with Vietnam yet to open their account.
It means that the Southeast Asians are eliminated while Australia must win their final Group D game against the Jordanians on Wednesday to progress -- and maintain their hopes of qualifying for the men's football competition at this year's Olympics.
The top three nations in the tournament are guaranteed of places in Rio.
The Australians had lost their opening match to UAE 1-0 so they were quickly on top of the Vietnamese, grabbing both goals from corners.
They opened the scoring in the second minute through James Donachie before his Brisbane Roar teammate Jamie Maclaren doubled the tally in the 60th minute from another set piece.
"It was a very tough game," Australia coach Aurelio Vidmar told the-afc.com. "I was really confident we would bounce back and that is what they did and we controlled the game for long periods of the game.
"(Vietnam) are well coached and well organised and they have made big improvements in the last few years. They have lots of 1995 born players that suggests they are investing in youth."