Captain Nick Malouf's team suffered mixed fortunes on Saturday's opening day of the London Sevens, the final stop on the World Series circuit, as they booked their quarter-final place but lost to their key rivals Samoa.
If Australia win their quarter-final tie against the formidable Fijians after both sides finished runners-up in their respective groups, then they will have sealed their spot at the 2024 Paris Games.
But Samoa, who play hosts Great Britain in Sunday's quarter-finals, can still pip them in the race for that final automatic spot if the Australians bow out in the last-eight.
The John Manenti-coached Aussies, who won the London tournament last year, currently have a nine-point lead in the series over the Samoans and remain in the driving seat.
But in their key clash on Saturday, the Samoans put the match to bed by halftime, running in three slick tries, aided by four missed tackles, to lead 19-0 at the interval.
Jimmy Turner was brushed aside in opening seconds, as Vaa Apelu Maliko went over and a double from Melani Matavao followed to give Samoa an unassailable lead.
There was an unfortunate accident in the second half when Samoa's Malo Lutero slipped just as he was trying to speed past Malouf and ended up being laid out by Malouf who had gone down low to tackle.
The captain was left hugely apologetic over the episode but Samoa still went on to win 24-14, repelling Henry Paterson and Nathan Lawson's second-half tries for the Australians.
The defeat, after Australia had opened up their defence with a five-try, 33-12 win over Spain, left the holders in the nervous position of a last-match, winner-takes-all clash with France to earn the quarter-final berth.
But the Australians made no mistake with Maurice Longbottom going over for two late tries after both Turner and Tim Clements had also scored in the 26-12 win.
Fiji, unusually still looking for their first Series triumph of the year, beat Ireland and Japan to book their last-eight clash with the Australians.
New Zealand, winners of five events this season in Sydney, Los Angeles, Hong Kong, Singapore and Toulouse, remain the team to beat, continuing their unbeaten streak with three comfortable wins over USA, Great Britain and South Africa in a formidable pool.
The Kiwis will play France, while Argentina face Ireland in the other quarter-final.
