The Matildas have suffered their heaviest and most humiliating defeat in 17 months, with an inexperienced line-up thrashed 5-0 by Canada.
Nichelle Prince scored a first-half brace to send Canada on their way, with Cloe Lacasse, Simi Awujo and Adriana Leon completing the rout inside 62 minutes on Saturday (AEDT).
It was Australia's heaviest defeat and poorest performance since a similarly inexperienced line-up suffered a 7-0 loss to Spain in June 2022.
Australia take on Canada in freezing weather. Source: AAP / Joel Carrett
Sam Kerr and Mackenzie Arnold were out injured while Caitlin Foord, Steph Catley, Mary Fowler and Kyra Cooney-Cross were among those benched amid heavy workloads at club level.
The starting line-up in Langford had a combined 429 caps, with 281 of those between Clare Polkinghorne and Tameka Yallop.
Charlize Rule and Sarah Hunter debuted at right-back and holding midfield and were among six players with less than 20 caps.
On a sodden artificial pitch at Starlight Stadium, the disjointed Matildas struggled to get to grips with the surface, or a brilliant Canada.
Australia were overrun in midfield and had no first-half shots to Canada's 13. It took just 10 minutes for the hosts to take the lead.
A heavy backpass from Rule sold Polkinghorne into trouble and as the centre-back got the ball caught under her feet, Prince pounced.
Hayley Raso (centre) races away after scoring in Australia's World Cup thrashing of Canada in July. Source: AAP / Victoria Adkins/AP
Teagan Micah made three brilliant saves, denying Leon in the 24th and 31st minutes and Vanessa Gilles in the 27th.
But in the 43rd minute, Ashley Lawrence burst down the right and cut back to Prince, whose first-time shot beat a disappointed Micah at the near post.
Four minutes into the second half, the defending Olympic champions all but sealed victory when Hunter dawdled on the ball and Lacasse pinched it off her, burst forward and scored.
In the 55th minute, Rule's clearing header fell to Awujo, who, under no pressure, had time to take a touch and fire home from distance.
Seven minutes later, Leon completed the rout when she drifted unmarked between a scattered defence to score.
Gustavsson turned to more experience in Fowler, Cooney-Cross, Katrina Gorry and Alanna Kennedy for the final half hour.
Australia had their first shot through Fowler in the 74th minute, with Kailen Sheridan making a comfortable save.
In her second-last game, retiring Canada great Christine Sinclair entered the fray in the 62nd minute.
The second friendly is in Vancouver on Wednesday afternoon (AEDT).
