Tries from the Australian connection of Marika Koroibete and Dylan Riley have secured Saitama Panasonic Wild Knights the inaugural Japan Rugby League One title.
The Wild Knights prevailed 18-12 over Suntory Sungoliath in sweltering conditions at Japan's National Stadium in Tokyo on Sunday.
Capped by Japan last year, Gold Coast-born Riley was involved in the lead-up to Koroibete's 28th minute try, drawing in two defenders to create the space for the Wallabies winger to score the game's opening five-pointer.
Centre Riley collected one of his own in the 73rd minute to push the Wild Knights out to their six-point winning margin.
Trailing 10-3 at halftime, Suntory were kept in the game by the boot of All Black Damien McKenzie, whose four penalty goals brought his side to within a point of the Wild Knights heading into the last 15 minutes.
The Wild Knights were missing their influential Japanese Test five-eighth Rikiya Matsuda but his replacement Takuya Yamasawa pulled off the play of the match just before halftime when he knocked the ball from McKenzie's grasp as he was diving for the tryline.
Despite some powerful charges from Wallabies midfielder Samu Kerevi, Suntory never threatened the Saitama goal-line again.
Kerevi and Koroibete are set to be involved in Australia's three-Test series against England in July.
The win was the former Wallabies coach Robbie Deans's fifth title with the Wild Knights, matching the five from his time in charge of the Crusaders in Super Rugby.
Fellow Aussies Jack Cornelsen, Ben Gunter and Semisi Tupou were part of the winning line-up, while the Kiwi pairing of flanker Lachlan Boshier and midfielder Vince Aso were also valuable contributors.
The fortunes were mixed for other Australians on the final weekend.
Former Wallabies playmaker Bernard Foley helped Kubota Spears to finish third after a 23-15 win over a Toshiba Brave Lupus side that featured Australian lock Hugh Pyle.
But Israel Folau will be playing in the second division next year after the Rob Penney-coached NTT Communications Shining Arcs lost the second leg of their relegation series 33-19 to the Mitsubishi Dynaboars.
Michael Cheika's NEC Green Rockets survived in the top section despite winning just one game all season, edging Honda Heat on points scored across a two-legged promotion play-off where each side won one match.