A Louise Quinn header was enough to earn Vera Pauw's side the friendly win.
A second-half header from Louise Quinn secured a historic win for the Republic of Ireland as they overcame Australia 3-2 at Tallaght Stadium.
Vera Pauw's snapped a losing streak by recording this deserved victory in front of 3,314 supporters at Tallaght Stadium against a team who finished fourth at the Tokyo Olympics.
It is Ireland's biggest win over a higher-ranked opponent in over two decades and they set off to achieve it straight away with Amber Barrett unleashing a stinging shot inside two minutes.
Australia barely had a chance to catch their breath when debutant Lucy Quinn curled a powerful free-kick at goal, which struck the post and rebounded in off goalkeeper Mackenzie Arnold.
The game was back and forth in many ways but Ireland were never outclassed by a team led by star striker Sam Kerr, who was marking her 100th appearance.
Mary Fowler twice got the visitors back into the contest, albeit with a bit of luck, but Ireland also profited when a strike from Denise O'Sullivan was deflected in.
At the end of a thrilling first half, it was 2-2 but Ireland will have felt that they were slightly on top. And they continued to play with confidence in the second period.
Louise Quinn powered in a header early in that half to reassert a lead that they would not surrender as Pauw's team showed how recent performances against top-quality opponents stood to them.
Ireland, who were roared on by a vocal crowd, finished the game by battling for every ball and proving that they belonged in competition against such a good team.
Next up is their 2023 FIFA Women's World Cup campaign, starting at home to Sweden on October 21st.
Republic of Ireland: Brosnan; Fahey, Louise Quinn, McCarthy; O’Gorman, McCabe; Finn (Caldwell 90), O’Sullivan, Barrett (Farrelly, 60); Payne (Kiernan 90), Lucy Quinn (Whelan 72).
Australia: Arnold (Williams HT); Polkinghorne, Kennedy (Checker HT), Nevin (Beard 68); Yallop (Gant 68), Logarzo (Wheeler 53), Cooney-Cross, Catley; Gielnick, Kerr, Fowler.
Referee: Paula Brady (Ireland).
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