A mixed performance from Australia confirmed their fourth Olympics appearance with a 2-1 away triumph over the Southeast Asian nation in Wednesday evening's away leg at the Cẩm Phả Stadium in Vietnam.
The match was played behind closed doors due to coronavirus fears, and kickoff was delayed due to a blackout at the ground, which then stopped play again just a minute into proceedings.
Ante Milicic's side arrived in Vietnam's Quảng Ninh Province with a 5-0 goal buffer following last Friday's win in Newcastle, and their advantage was built upon thanks to first-half strikes from Sam Kerr and Hayley Raso.
It could have been a bigger margin at the break, but Kerr hit the woodwork from a sharp chance and Chloe Logarzo saw her penalty attempt saved, with Kellond-Knight fluffing the follow-up shot.
Huynh Nhu scored Vietnam's first-ever goal against Australia in the second half at the Cẩm Phả Stadium, after a sloppy back-pass from Alanna Kennedy left Australia's goalkeeper, Lydia Williams, stranded.
Korea Republic will battle with China PR for the other AFC Olympic qualification spot, with Japan having already qualified as tournament hosts.
Australia's preparations for the Tokyo 2020 Olympic Games continue in April with two international friendlies against World Cup winner United States of America and Canada, on April 10 and April 14.
