|First blood to Australia who take a 1-0 lead in the best-of-three finals and can wrap up victory in the series with a win in Adelaide on Tuesday [GETTY]
Australia salvaged a 15-run win after snuffing out an unlikely Sri Lanka tail-end comeback in the last over on Sunday to take a 1-0 lead in the best-of-three tri-series finals.
David Warner belted 163 from 157 balls, his maiden ODI hundred, and shared a 136-run opening stand with Matthew Wade (64) to set Australia on course for an imposing 321-6 after Michael Clarke won the toss and elected to bat at the Gabba.
Sri Lanka were down and seemingly out of the contest after slumping to 144-6 in the 31st over chasing 322 to win, but Nuwan Kulasekara inspired an unlikely fightback with a career-high 73 from 44 balls and combined with Upul Tharanga (60) in a 104-run partnership from 70 balls.
David Hussey ended the partnership in the 42nd over but the lower order continued, with Dhammika Prasad scoring an unbeaten 31 to keep the match alive until No. 11 Lasith Malinga was out and Sri Lanka were dismissed for 306 in 49.2 overs.
Shane Watson took the last three wickets to finish with 3-33, ending Australia's three-match losing streak against Sri Lanka.
Australia can clinch the finals series with a win in Adelaide on Tuesday, although Warner is in some doubt after straining his left groin and not fielding on Sunday night.
Clarke said the Australians wouldn't stand a chance in game 2 if they bowled and fielded like they did on Sunday night.
"We've got to be better than that,'' he said.
"We're supposed to be the No. 1 one-day team in the world - we have to execute better than that.''
Clarke, who recovered from a back injury to play the match, praised the batsmen for posting a 300-plus total but was disappointed with the bowling in the power plays and in the crunch moments between when Brett Lee (3-59) and part-time spinner David Hussey (4-43) got wickets up front and Watson returned in the dying overs to finish off the Sri Lankans.
D Warner b Prasad 163
M Wade c Herath b Kulasekara 64
S Watson c Thirimanne b Maharoof 21
D Christian c Sangakkara b Prasad 10
D Hussey c & b Herath 1
M Clarke c Jayawardene b Malinga 37
M Hussey not out 19
Total (for six wickets, 50 overs) 321
Fall of wickets: 1-136 2-186 3-223 4-224 5-288 6-321
Sri Lanka innings
M Jayawardene c Wade b Lee 14
T Dilshan b Lee 27
K Sangakkara c Watson b Lee 42
D Chandimal c Pattinson b D. Hussey 14
L Thirimanne c Wade b Hussey 14
U Tharanga c Hussey b Watson 60
F Maharoof c Christian b Hussey 8
N Kulasekara c Doherty b Hussey 73
D Prasad not out 31
R Herath c Doherty b Watson 5
L Malinga c Hussey b Watson 1
Total (all out; 49.2 overs) 306
Fall of wickets: 1-39 2-52 3-93 4-115 5-125 6-144 7-248 8-285 9-301 10-306.
"Warner and Wade were outstanding at the top,'' he said.
"Watson saved us once again, we are glad to have him back in the team.''
With rain threatening throughout the Sri Lankan innings after disrupting play twice while Australia was batting, the Duckworth-Lewis equation loomed as a potentially decisive factor.
After falling well behind the target rate when the top order crumbled, the tailenders got it back within easy range in the last six overs.
"We fought to the end ... It's a good attitude to have,'' Sri Lanka skipper Mahela Jayawardene said.
"It was an incredible partnership. (Kulasekara) did very well, lots of positives for us to take from this.''
Kulasekara's seven boundaries and three sixes - including two over deep mid-wicket off consecutive balls from David Hussey just before he got out - restored interest just when the match had threatened to get stale.
Earlier, Warner hit 13 boundaries and two sixes before he was bowled by Prasad on the last ball of the Australian innings.
He was impressive right through the innings, sharing the big opening stand with Wade, 50 for the second wicket with Watson (21) and 64 for the sixth-wicket with Clarke, who scored 37 from 25 balls after dropping himself down the order to give big hitters Dan Christian (10) and David Hussey (1) a chance in the batting power play.
Mike Hussey hit two sixes and was unbeaten on 19 from 10 balls.
Warner had a reputation as a big hitter with a rapid strike rate, but had underachieved in his first 18 ODIs, averaging 22.5 with a highest score of 74. The 25-year-old lefthander scored two centuries in six Test matches - a format few predicted he would succeed in due to his heavy hitting - and has now produced the goods in ODIs.
Warner, one of only seven Australians to score 150 or more in an ODI, said he'd been confident he would eventually reach triple figures if he played to his instincts and kept looking to score runs.