Australia 221 for 0 (Sutherland 109, Litchfield 106), beat Ireland 217 (Prendergast 71, Garth 3-34, Gardner 3-38) by 10 wickets
Phoebe Litchfield became the second youngest Australian woman to hit an ODI century en route to taking her country to a comfortable 10-wicket win over Ireland in Dublin.
Chasing 218 for victory, Litchfield hit an unbeaten 106 and Annabel Sutherland hit 109 not out to help Australia reach the target in 35.5 overs.
The win wrapped the series up 2-0 for Australia and ended their northern summer tour after drawing the multi-format Ashes series with England to retain the Ashes.
Playing without Alyssa Healy, Ellyse Perry, Meg Lanning, Rachael Haynes or Megan Schutt in an international for the first time in 14 years, Australia showed a glimpse of the future in the win.
Irish-born seamer Kim Garth took 3 for 34 against her old side, while Ashleigh Gardner also claimed 3 for 38.
In reply, Sutherland and Litchfield took hold as both struck their maiden white-ball international centuries. Sutherland's 109 from 101 balls included 11 boundaries, while Litchfield's 106 from 114 featured 14 fours.
At 20 years and 101 days, the NSW prodigy also became the youngest Australian woman other than Meg Lanning to score a century in a 50-over match.
"It means a lot," Litchfield said. "We spoke about trying to have a better start up top, and I have been pretty dry in the runs column. So for Bellsy [Sutherland] and I to go out and win the game, was pretty cool."
The win came after Healy and Perry were both ruled out of the match and withdrawn from The Hundred in England through injury.
Perry hurt her knee while batting in Australia's ODI win over Ireland on Tuesday, and has now been ruled out for up to six weeks with the injury.
And after battling through the Ashes with a fracture in her left index finger and right ring finger, Healy suffered a fresh break in her index finger on Tuesday after another blow.
Australia expect both to be fit to return for their next international against West Indies in early October, while Litchfield will replace Healy at the Northern Superchargers in The Hundred.
Healy and Perry's absences do come as a sizeable blow to The Hundred, given they are two of the biggest names in women's cricket.
Fellow Australian Heather Graham pulled out of the tournament earlier this week due to a calf injury, while Mitchell Marsh and Glenn Maxwell will both skip the men's Hundred to manage their workloads.