Australia moved to the top of the Cricket World Cup standings after beating Sri Lanka by 87 runs at the Oval.
Captain Aaron Finch lost the toss again and was made to bat first, but he spearheaded Australia's effort with a career-best 153 in a total of 334-7.
Counterpart Dimuth Karunaratne tried to inspire his side the same way, but after he was out for a career-best 97 in the 33rd over, Sri Lanka collapsed. From 186-2 to 247 all out, the last eight wickets fell for 61 runs.
Mitchell Starc took 4-55, Kane Richardson 3-47, Pat Cummins 2-38 and Jason Behrendorff, making his World Cup debut in place of Nathan Coulter-Nile whose back stiffened up, took a wicket.
Australia's fourth win from five matches lifted it above New Zealand and England to lead the tournament halfway through its group stage matches.