Pallekele, June 15 (IANS) Glenn Maxwell, the architect of Australia's two-wicket win in the rain-affected opening One-day International against Sri Lanka here late on Tuesday said he was just trying to hang on for as long as he could, given the mammoth 300-run target set by the hosts, adding the key to his unbeaten 80 on the day was taking calculated risks.

Sri Lanka scored 300/7 on a batter friendly pitch in the opening ODI of the five-match series before the tourists overhauled the revised target of 282 runs in 42.3 overs.

"I was just trying to stay out there as long as I could. I knew I was going to get balls to score off in my areas at some stage, and I was just trying to take risks at the right time," Maxwell said, summing up the morale-boosting win.

"I think when there was only three overs left, I think that was a good opportunity to try and get the run rate down under six, and then (I) try and do it in the next over without letting it get to the last over, because all sorts of chaos could happen in the last," added the all-rounder.

Sri Lanka looked ahead for much of the ODI but Maxwell finished with 80 not out off 51 deliveries, hitting a total of 12 boundaries, to steer his side to a comfortable win (DLS) with nine balls to spare.

Wanindu Hasaranga looked to be impacted by his persistent leg trouble, though the star all-rounder continued to showed his world-class talent once again, smashing 37 off 19 balls, embellished with six boundaries to guide the hosts to 300.

As the hosts looked poised to post a score around the 280 mark, the right-hander struck five consecutive boundaries off Jhye Richardson, manipulating field with smart footwork and a mix of touch and power. He returned to trouble the Aussies with the ball. He returned superb figures of 4/58 from nine overs and dismissed Aaron Finch and Marcus Stoinis, as well as Alex Carey and Pat Cummins in the same over.

Despite his exploits, Hasaranga could not land the killer blow on Royal Challengers Bangalore teammate Maxwell. The leg-spinner's final delivery beat the bat, though Maxwell scurried through for a bye to retain the strike, and then went on to plunder 15 off the next over.

Young Dunith Wellalage also tasted success on debut, taking two Australian wickets. After bursting onto the scene at the ICC Men's U19 Cricket World Cup, Wellalage earned a first senior international call-up and he didn't disappoint on Tuesday night.

The left-arm orthodox spinner claimed Steve Smith as his first scalp, forcing an error from one of the world's best as his delivery skidded underneath the Australian's bat. He was then entrusted with a death-over role, and claimed Ashton Agar with a plumb lbw decision that looked to turn the tide.

Despite the debutant's best efforts, Wellalage was outfoxed by Maxwell, with a reverse sweep and a swat to the leg-side for consecutive boundaries bringing the required rate down from eight to six.

Finishing with 2/49 from seven overs, Wellalage will be all the richer for the experience though, and captain Dasun Shanaka predicts the all-rounder will feature a lot more for the senior team.

"He's is a very good cricketer. I have seen him performing through the under-19 level, so I think he'll deliver in the future for us."

Brief scores: Sri Lanka 300/7 in 50 overs (Danushka Gunathilaka 55, Pathum Nissanka 56, Kusal Mendis 86 not out) lost to Australia 282/8 in 42.3 overs (Aaron Finch 44, Steven Smith 53, Marcus Stoinis 44, Glenn Maxwell 80 not out; Wanindu Hasaranga 4/58) by two wickets (DLS).