Australia are well placed to complete the one-day series in positive fashion after running through the Sri Lankan middle and lower order, with the home side dismissed for just 195 in the fifth one-day international.
Australia lost the toss for the fourth time in succession, but the Sri Lanka batsmen were unable to make use of a decent batting pitch in Pallekele despite many getting starts.
The wickets were shared between six Australian bowlers, with fast bowler Mitchell Starc (3-40) once again in damaging form.
Leg-spinner Adam Zampa (2-43) also continued his good series, taking two top-order wickets.
The impressive effort in the field came at a cost, with big-hitting opener Aaron Finch forced from the field with an injured index finger after a failed attempt to complete a difficult catch at first slip.
Things began brightly for Sri Lanka as captain Danushka Gunathilaka (39) and fellow opener Dhananjaya de Silva (34) put on 73 at nearly a run a ball.
But the home side lost three wickets in nine balls and the steady flow of wickets continued throughout the innings as the run-rate slowed.
Part-timer spinner Travis Head (2-22) made an unexpected double breakthrough, his lbw dismissal of Kusal Perera was controversially confirmed by the third umpire despite an apparent inside edge.
Only some late hitting from Sachith Pathirana boosted the tally, before he was the last man out for 32 off 38 deliveries with Sri Lanka dismissed after 40.2 overs.