The Olyroos have shown no fears on the world's biggest stage, upsetting a 10-man Argentina in Sapporo on Thursday night.
Twenty-four hours after the Matildas began their Olympic campaign with a win in Tokyo, Lachie Wales and substitute Marco Tilio's goals fired Graham Arnold's men to a 2-0 victory over an international football powerhouse. In a controversial game, where nearly a dozen cards were handed out, Fransisco Ortega's send off late in the first half proved the turning point.
The result means Australia jumps to the top of Group C after Egypt and Spain played out a 0-0 stalemate earlier in the day.
"We always believed in what we wanted to achieve, we got here early and had a really good training camp inIchihara," Wales told the Seven Network.
"We always believed in Arnie's philosophy and we used words like 'belief'. Believe it, receive it and it happens. It's a dream come true for all of the boys. It's one game, but hopefully we can get another win against Spain (on Sunday).
"To all of the Australians out there, it's such a big moment in football. The opposition tonight is one of the biggest nations in the world and tonight we shocked the world, and hopefully we can keep shocking the world as we move on through the tournament."
The Olyroos took just 14 minutes to strike first on Thursday night.
The team moved the ball quickly to Joel King out wide, whose low cross found Wales' feet and he tapped home their opening goal.
But Argentina continued to play positively, with Carlos Valenzuela and Fausto Vera among their players to come close to scoring.
The pressure continued to build on the Aussies, but on the counter-attack, the ball fell to Riley McGree inside the box, who attempted a bicycle kick which was stopped by goalkeeper Jeremias Ledesma. The Olyroos then again found King in space down the wing, with his cross finding Wales whose shot hit the woodwork. However, it didn't matter as the linesman ruled off side.
There was huge drama in added time when Argentina were reduced to 10 men, after Ortega received two yellow cards in the space of 30 seconds.
The Olyroos led 1-0 at half time.
Graham Arnold's men came firing out of the blocks after the break, with Mitch Duke and Daniel Arzani piling on pressure inside their front third.
But it was Argentina who started to pile on the pressure, with several Olyroos players receiving yellow cards. Fans back home in Australia then collectively held their breath when Santiago Colombatto found the back of the net after 55 minutes, however, the linesman had raised his flag.
With 20 minutes left, the Olyroos appeared to have doubled their advantage when McGree found himself in space and passed to Wales, but he couldn't beat a desperate, lunging Ledesma.
However, it didn't matter as Tilio's superb strike in the 80th minute - less than 90 seconds after being subbed on by Arnold - gave his side an unassailable 2-0 advantage.