The Aussies had seven different try-scorers at Thomond Park in Limerick, creating a selection headache for head coach Tim Sheens ahead of their quarter final clash against the USA Tomahawks next week.
The game started looking like itd end up in a cricket score when Jarryd Hayne crossed the white line after less than 90 seconds off the back of a Brent Tate pass, but Ireland dug deep.
The next 20 minutes saw the Wolfhounds have to face repeated sets from the Kangaroos after coughing up penalties, resulting in Cooper Cronks first of two tries.
The end of the first half saw three quick tries to the Kangaroos, with Daly Cherry-Evans putting Greg Bird over with a short inside pass.
Brett Morris scored two minutes later after picking up a loose ball, and then right on the half-time buzzer Billy Slater skipped away from the Irish defence to take a 26-0 lead into the half time break.
The opening 15 minutes of the second half werent pretty, with a high error count from both sides, before Cronk scored his second try after picking up a bullet pass from Corey Parker.
With Smith switching places with Farah for the second half, Parker overtook the goal-kicking, and converted Cronks try.
Man of the Match Daly Cherry-Evans earned his award after collecting his own grabber kick to score for the Kangaroos.
Shortly after, Andrew Fifita bolted through a gap in the Irish defence to score a try, with Jarryd Hayne notching up the half-century with his second try to finish the match.
Australia 50 (Hayne 2, Cronk 2, Slater, Fifita, Cherry-Evans, B Morris, Bird tries; Smith 3, Parker 4 goals)
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