England began the game with three players from Sunday’s final win against Pakistan in Buttler, Phi Salt and Chris Jordan.
Buttler’s vice-captain Moeen Ali had warned the timing of the series was “horrible”, and it was always going to be a challenge for England to avoid a World Cup hangover.
But one of their T20 mainstays Dawid Malan, absent from the last two matches of the tournament with a groin injury, offered the leading resistance in a total of 287-9.
Malan is adamant 50-over cricket is his best format of the game and backed that up with 134 runs off 128 balls, which included 16 boundaries.
But the support the rest of the England batting line-up provided was limited, only Buttler and David Willey offering up much back-up with 29 and 34 respectively. Pat Cummins and Adam Zampa were the pick of the home bowlers with three wickets apiece.
David Warner and Travis Head effectively set up the win with an opening-wicket partnership of 147 inside 20 overs before Head holed out to Salt off the bowling of Jordan.
Two quick wickets for Willey – Sam Billings catching Warner in the deep and Buttler pulling off a diving catch to remove Marnus Labuchagne cheaply – briefly stemmed the tide of runs.
But Warner had already scored a run-a-ball 86 and Head 69 from 57 leaving Australia’s third half-centurion Steve Smith (80 not out) to steer Australia to the win with a 28th ODI 50 with three overs remaining.
The second match takes place on Tuesday with England expected to welcome back a number of their T20 World Cup stars, including Adil Rashid and Sam Curran, who were both rested for this ODI opener.