An injury concern and a fighting loss to Spain have slowed the underdog Gangurrus' Paris push.
Australia's 3x3 women's basketball team lost 21-17 in a physical clash on Friday at La Concorde that ended a four-game Olympics winning streak.
An apparently hobbled Lauren Mansfield didn't play, leaving Alex Wilson, Anneli Maley and Marena Whittle to slug it out in the highly physical first-to-21 match.
The Australians, who stormed to a surprise qualification tournament win and sealed their Olympic debut in the sport's second appearance, had led the pool after a 21-12 win over Azerbaijan earlier in the day.
That made it four-straight after a first-up loss, Whittle's eight points powering them to a comfortable win.
The top two countries will progress automatically to a semi-final while four others fight for the right to play them.
Australia are still a chance to bypass that play-off if they beat France in their final round robin game on Saturday.
Australia led Spain 5-1 before Vega Gimeno and Sandra Ygueravide (nine points apiece) found their range.
Wilson and Whittle found joy in the pick-and-roll but a combined one-of-six from outside the arc - worth two points in 3x3 - and some costly misses around the rim hurt.
Down 18-17 the Australians missed three lay-up attempts that would have tied the game.
Spain then drew clear before a Maley foul under the rim led to the match-winning bucket.