Clint McKay took five wickets as Australia's bowlers suffocated Sri Lanka's normally free-scoring batsmen to wrap up the One-day International Tri-series with a 16-run victory in the third and deciding final at the Adelaide Oval on Thursday.
Australia selected two spinners but it was the quicker bowlers who made the difference with the outstanding McKay (5-28), Brett Lee (3-29) and stand-in skipper Shane Watson (2-13) all contributing as they dismissed Sri Lanka for 215 with six balls remaining.
Australia will now retain the number one ranking in the one-day international championship for a third successive year unless they lose all five matches on their upcoming tour of West Indies.
The Sri Lankans, who won the toss and elected to field, would have been delighted with their victory target of 232 after chasing down 272 with ease on the same ground two days ago to level the series.
Their top order departed cheaply, however, and when skipper Mahela Jayawardene was bowled by McKay for 15 they were reduced to 53 for four and the match was in the balance.
Lahiru Thirimanne (30) and Upul Tharanga, who hit a defiant 71 from 122 balls, steadied the innings with a 60-run partnership for the fifth wicket but the Australians managed to take key wickets at important moments.
Watson removed Thirimanne and Tharanga, both caught, and McKay returned to seal the victory with by bowling both Rangana Herath (0) and Lasith Malinga (6).
Earlier, Australia had made a steady start to their innings but suffered a middle-order collapse to slump from 115 for one to 177 for seven, triggered when Herath brilliantly caught Watson for 19.
Herath also made an immediate impact with his left-arm spin, having Australia's top scorer Matt Wade (49) caught with his first delivery and bowling Peter Forrest (3) before finishing with figures of three for 36.
Farveez Maharoof (3-40) was equally influential and took the wicket of dangerman David Warner, who scored 163 and 100 in the first two matches of the final, for a quickfire 45.
McKay (28) and Lee (32) shared a stand of 40 for the seventh wicket but three deliveries remained when Nathan Lyon, making his one-day international debut, was the last man out with just 231 on the board.
India were the other team in the Tri-Series.