Eddie Jones said Thursday he hoped Australian fans would roar on his Japan side when they face Ireland north of Sydney in July, and then again a year later at the Rugby World Cup.
Japan as hosts famously upset Ireland in the 2019 World Cup and the two sides will lock horns again in a Nations Championship test in the New South Wales city of Newcastle on July 11.
It will be the first neutral test played in Australia since before the Covid-19 pandemic.
"It's a great experience for us to play here, get used to the environment, maybe become the team in Newcastle," Japan head coach Jones told reporters at the city's stadium.
"You know, when we play up here in the World Cup, we want all the Newcastle people to support Japan," said the Australian.
Jones said the test against the world's third-ranked side would be invaluable for his players ahead of Japan's opening World Cup match against Samoa at the same venue on October 3, 2027.
"We'll be up here for a week for the Samoa game. So it's how you can maximise your preparation for that week," said Jones.
"It's really important because we'll have, you know, a relatively young team for the World Cup.
"And you talk to players about their experience of a World Cup, particularly young players, and they can't remember anything, right, because it becomes a blur?
"So having had the experience of playing in this ground, just that little bit of familiarity will definitely be a potential advantage."
Jones said that Ireland's rise to the top echelons of the world rankings was an inspiration for smaller rugby nations.
"Ireland's a great example of what you can do with a small population," said the former Australia and England coach, now in his second spell in charge of Japan.
"Five million people have become a top-four team in the world by really maximising the talent they've got.
"And, you know, that's a challenge for Japan, as it is for Australia at the moment, to do the same sort of thing.
"So they're a good team, tough team, smart team, so we're looking forward to playing against them."
Irish Rugby Football Union president John O'Driscoll said he expected the game would draw a "huge" number of expat fans to the 30 000 capacity stadium.
The inaugural men's Nations Championship will this year pit the northern hemisphere's Six Nations sides against New Zealand, South Africa, Australia, Japan and Fiji in a series of tests.
The winner will be crowned at a finals weekend played at Twickenham in November.
The Rugby World Cup in Australia kicks off on October 1, 2027, when the hosts face Hong Kong in Perth.