Darwin born Jessica Mauboy is credited as being the reason Australia has a place on the stage in the Eurovision song contest.
She is the second Indigenous Australian to compete after Isaiah Firebrace last year.
Her guest performance at Eurovision in 2014 trialed Australia's place on the European stage, with Australia invited to officially compete the following year.
But four years after that celebrated performance, Mauboy's grand final show in Lisbon is the first time Australia placed outside the top 10.
In 2015, Guy Sebastion placed fifth; in 2016, Dami Im came second, and last year Isaiah Firebrace came ninth.
Mauboy and her song 'We Got Love' came in at number 20, with her jury vote of 12th scaled down with the lowest score from the tele vote.
Eurovision is known for its extravagant and outrageous routines, costumes and props; Mauboy performed solo while the night's winner Israel's Netta Barzilai incorporated chicken noise loops - and dance moves - into her song 'Toy'.
"I really, honestly felt like I gave my all and sang my heart out as much as I could," Mauboy told reporters after the final.
With Australia rallying around Mauboy, Eurovision historian John Kennedy O'Connor told ABC Radio National on Monday "she was terrible".
"It was dreadful. She was describing herself in the media as Australia's Beyonce. Clearly she's never seen Beyonce."
The author of The Eurovision Song Contest: The Official History went further, questioning whether Australia will be allowed to stay in the competition.
"I think your welcome has now been rescinded and I don't say that with any glee."