Coming out firing in the first quarter, it was a back and forth affair from both sides with Australia struggling to deal with the pace of Japan and the shooting Makoto Heijima as well as the size of Ira Brown, testing the Boomers' defence early.

Daniel Kickert got Australia rolling though, knocking down a quick eight points in the opening term while he went on to record a game-high 22 points by the final siren which included 4-4 three-point shooting.

Kickert's role was not restricted to his scoreboard influence though, pulling in seven rebounds while also dishing out three assists to drive his team to victory.

“Everyone's confidence exudes and spreads throughout the group," Kickert said.

"We have this confidence about us that we can pull through games."

That confidence was on show from beyond the arc as the Boomers hit 9-21 from deep as well as 55% from inside, benefited by an overall size advantage that eventually wore Japan down.

Mitch Creek covered Japan’s star Brown which allowed Matt Hodgson and Kay (seven offensive rebounds) to grab 19 board between them while also restricting their opponent's second chance opportunities by giving up just four offensive boards.

Hodgson was also able to do work in the post, finishing with ten points of his own as he enjoyed an imposing performance under the rim.

Kay was the top rebounder for the game with 10.

After a sluggish start, the second term was a different story for the hosts and as they rained triples, the lead began to extend beyond Japan's grasp.

Chris Goulding was the instigator, finishing with eight points that helped swing the momentum of the game in the Boomers favour.

The free-flowing offence allowed nearly every Aussie on the court to hit the scoreboard with Cameron Gliddon the fourth Australian to reach double digits, scoring 10 points on 4-8 shooting from the field.

A couple of sloppy turnovers in the third quarter allowed Japan back into the contest and they cut the deficit to six points at one stage before Nathan Sobey showed off in front of his Adelaide fans with a highlight alley-oop play.

The final quarter saw Australia find another gear that Japan could not match and when Kickert, Cadee and Gliddon each knocked down three's, the game was clinched.

Lucas Walker, a late replacement for Angus Brandt who was suffering from an illness, hit the court in the dying seconds and to the delight of the crowd, drained a mid-range jumper to finish off the contest.

With two wins from the first window, the Boomers sit at the top of their group and they now look to the second qualifying window in February where both games will be played in Australia.

For now, the team will disperse and resume their NBL duties before regrouping in the New Year to take on the Phillippines and Chinese Taipei.