David Warner was not his usual destructive self but effective nevertheless, his first international century since completing the ball-tampering ban setting up Australia's 41-run win over Pakistan
David Warner and Aaron Finch made a strong start, adding 146 runs for the first wicket.
Amir took 5/30, but his effort was not enough as Pakistan suffered their second defeat of the showpiece event.
Pat Cummins took 3 wickets for Australia, while Kane Richardson took 2. Aaron Finch also bowled two overs and dismissed Mohammad Hafeez.
The duo of Sarfaraz Ahmed (40) and Wahab Riaz (45) gave the Australians a scare with a rearguard action that revived their hopes for a while.
Mitchell Starc closed out the game at the death, dismissing Wahab and Mohammad Amir in a single over.
Australia are now 2nd in the points table, while Pakistan are 8th.