Australia 282 for 8 (Maxwell 80*, Smith 53, Hasaranga 4-58) beat Sri Lanka 300 for 7 (Mendis 86*, Nissanka 56, Gunathilaka 55) by two wickets (D/L method)
Kandy: Maxwell finished with 80 not out off 51 deliveries, hitting a total of 12 boundaries, to steer his side to a two-wicket win via the DLS method.
Sri Lanka looked ahead for much of the first ODI in Pallekele, only for Glenn Maxwell to turn the match late in the tourists' favour.
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.
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.
Finishing with 37 from 19 balls, Hasaranga helped the hosts reach an even 300 before troubling the Aussies with the ball.
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.
After bursting onto the scene at the ICC Men's U19 Cricket World Cup, Dunith Wellalage was no shrinking violet after earning a first senior international call-up.
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.