The Boomers have lost 93-83 to Canada in a high-quality Olympic basketball battle that leaves Australia needing to fell Giannis Antetokounmpo's Greece to ensure a quarter-final berth.
Australia played wonderfully in Lille on Tuesday to lead by four points at halftime, before Shai Gilgeous-Alexander, RJ Barrett (24 points, seven rebounds, five assists) and their NBA support cast overwhelmed them to seize control of their Olympics pool of death.
Gilgeous-Alexander was practically unstoppable for the World Cup bronze medallists, scoring 16 points in just 25 minutes on eight-of-10 shooting.
"They just pressured us really well, turned us over a little bit," Boomers centre Jock Landale said.
"On top of that, they made tough shots. All through the game, they made tough shots."
Josh Giddey had won the earlier exchanges (19 points, seven rebounds, six assists) before his former Oklahoma City teammate took control in the second half.
Tokyo bronze medallists Australia, who impressively beat Spain in their Games opener, will play the winless Greece on Friday.
Victory would likely see them finish second and earn a ticket to Paris's quarter-finals, while a loss would likely leave them among a pack of teams hoping to be there as one of the two best-performed, third-placed teams.
Landale said they took no solace from pushing a side that will fancy its chances of taking down the United States later in the tournament.
"No, mate; we're one of those teams as well," he said.
"We just didn't get the job done tonight."
Things began brilliantly as Australia shared the love in Lille, highly-efficient offence and swarming defence offsetting the brilliance of emerging NBA superstar Gilgeous-Alexander in the first half.
Patty Mills and Jack McVeigh hit crucial triples, Landale (16 points, 12 rebounds) was clever around the rim, Dante Exum (15 points) impactful in his injury return and Dyson Daniels again a problem on defence as they led by as many as six.
But Canada put the heat on Giddey and the Boomers began to leak turnovers - half of their 18 came in the third quarter - Lu Dort firing up to put them 10 clear.
Exum's return changed the mood though, the Dallas guard driving to the rim and sparking a comeback that, after two late McVeigh triples, had Australia down by two at the final break.
They couldn't buy a bucket in a 21-13 fourth quarter, Gilgeous-Alexander icing the cake with a neat alley-oop pass to Dwight Powell for an 11-point lead with one minute to play.
Mills (eight points on two-of-10 shooting, four turnovers) struggled while Joe Ingles and Matthew Dellavedova weren't used.
Brian Goorjian also held back centre Duop Reath, despite the Boomers being one-point better off during his nearly four minutes on court.
McVeigh (nine points) hit three-of-five triples but the team was eight-of-25 from beyond the stripe, while Josh Green was scoreless and made just two field goal attempts in 18 minutes of court time.
Earlier, Spain boosted their hopes of progression with a 84-77 defeat of Greece, Santi Aldama the hero with 19 points and 12 rebounds.
Antetokounmpo had 27 points and 11 rebounds for Greece.