Sri Lanka scored 283-7 to overhaul Australia\'s 280-6 with four balls to spare.
Hobart: Mahela Jayawardene hit an aggressive half century to help set up Sri Lanka's thrilling three-wicket win over Australia in a limited-overs tri-series match on Friday.
Man of the match Jayawardene hit six boundaries and a six to make 85 off 81 balls, and Dinesh Chandimal brought up an assured 80 at Bellerive Oval as the Sri Lankans scored 283-7 to overhaul Australia's 280-6 with four balls to spare.
"It was one of those days when most of your shots went to the gaps," Jayawardene said.
Sri Lanka now leads the tri-series with 15 points, one more than Australia, ahead of the finals starting March 4.
"The youngsters are learning a lot from these games," Jayawardene said. "We are top of the table, but we still need to do a lot of hard work."
Sri Lanka's hopes of the win looked in doubt when Angelo Mathews miscued a Dan Christian (3-53) delivery with 14 runs required from nine balls, but Thisara Perera hit a four and a six off the next two balls, and Nuwan Kulasekara hit a four in the last over to seal the victory.
"Unfortunately we couldn't get over the line, but full credit to Sri Lanka," Australia captain Michael Clarke said. "Our execution with the ball wasn't good and the top four could do better."
Sri Lanka opener Tillekeratne Dilshan made just 3 before he was caught by Peter Forrest at deep square-leg off Ben Hilfenhaus in the eighth over.
Kumar Sangakkara edged a Christian ball to David Warner for 22, and Jayawardene was stumped by wicketkeeper Matthew Wade when he was beaten by a Xavier Doherty delivery.
Lahiru Thirimanne added 24 before becoming Christian's second victim, caught by Hilfenhaus.
Chandimal hit seven fours in his knock. He was trapped lbw by Ryan Harris and Farveez Maharoof had added just 5 when he lofted a ball to Harris off Hilfenhaus.
Forrest earlier scored 104 for his maiden international century in what appeared to be a challenging Australian total. His century was the first of the tri-series tournament, which also involves India.
Clarke made a quick-fire 72 off 79 balls in a 152-run, third-wicket stand with Forrest to steady Australia after an early collapse.
Australia made a poor start to the match after winning the toss and opting to bat when opener Matthew Wade was caught by Jayawardene at wide mid-off for 5 in just the second over.
Opening partner Warner was caught behind for 7 shortly after while defending a Maharoof delivery.
Perera claimed an athletic catch on the mid-wicket boundary to give Mathews (2-43) the valuable wicket of Australia captain Clarke.
Forrest had hit 10 boundaries and two sixes when he offered a simple catch to Maharoof off a slower Mathews ball.
Michael Hussey made 21 off 14 balls before being bowled by Lasith Malinga and Christian was stumped by wicketkeeper Sangakkara after he charged up the wicket at a Rangana Herath delivery.
David Hussey was unbeaten on 40 with Brett Lee on 20 at the end of the Australia innings.