David Warner and Mitchell Marsh both made centuries as the openers pummelled Pakistan in their World Cup clash at the M. Chinnaswamy Stadium in Bengaluru on Friday.
The pair put on 259 for the first wicket.
Warner reached his 21st ODI century off 85 balls with seven fours and six sixes with Marsh completing his ton from 100 deliveries, hitting 10 fours and six sixes.
Marsh's century came on his 32nd birthday while Warner was dropped by Usama Mir off Shaheen Shah Afridi when he had made just 10.
Marsh was eventually dismissed for 121 when Mir successfully held onto a chance off Shaheen.
Pakistan made one change from the team defeated by India with Mir coming in for fellow leg spinner Shadab Khan.
Australia are unchanged following their win against Sri Lanka, their first in the tournament after two opening losses.
Pakistan have two wins and one defeat.
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