Accompanied by a trio of Portuguese guitar players, she performed a unique version of her single Fallin’ before treating the crowd to a barnstorming rendition of We Got Love.
"It’s been such an incredible journey, it’s huge, it’s massive. I’ve had goosebumps the whole way,” she told the crowd.
This isn’t Mauboy’s first Eurovision experience, she performed as an interval act at the 2014 contest.
She says she had always wanted to return.
"I had unfinished business. Having had that first taste of it, I couldn’t let it go.”
Asked by SBS Eurovision commentator Joel Creasy about the motivation behind We Got Love, Mauboy explained it was based on events at the time.
“There was a lot of things happening around the world, we’d just had marriage equality pass in Australia,” she said.
“Love was the first word that came to me. Love comes in so many ways. It can lie, it can be truthful, you can feel celebrated, but you can also feel hurt.”
The rooftop party was thrown by SBS in conjunction with Australia’s Embassy in Portugal.
Ambassador Peter Rayner says there are more Australians in Lisbon this week than any time in recent memory.
He thinks Mauboy is the perfect person to sell Australia to the Portuguese.
“We have very friendly relations with Portugal, but to be frank, they’re not substantial,” he told SBS News.
“We’d like to do more in that regard, so this is starting to really put Australia on the map.”
SBS Managing Director Michael Ebeid told guests interest in the song contest has exploded since Australia’s participation began in 2015.
“The love for Eurovision’s just grown and grown, whether it’s the quirkiness, the kitch, the culture, who knows; it’s probably a combination of all three.”
After a few hectic days of appearances and performances, Jess was finally able to get some downtime to rest her voice, ahead of her dress rehearsal for the second semi-final.
She’ll compete in the early hours of Friday morning Australian time, in a bid to secure a place in the weekend’s final.
Watch Eurovision live on SBS at 5am or live stream it on SBS On Demand.
