While Japan have already secured their spot for the showpiece event, Australia still have work to do.
If the Socceroos (13 points) fail to beat Japan at Optus Stadium on Thursday night, their hopes of automatic qualification could rest on the result of next Tuesday's clash with Saudi Arabia (10 points) in Jeddah.
Japan have brought an inexperienced squad to Perth with overseas stars such as Kaoru Mitoma (Brighton & Hove Albion), Daizen Maida (Celtic), Reo Hatate (Celtic), Takumi Minamino (Monaco), Ritsu Doan (Freiburg), Junya Ito (Reims) and Hidemasa Morita (Sporting Lisbon) among the big outs.
But don't be fooled, Japan are still desperate for victory, with the Samurai Blue keen to maintain an unbeaten run against Australia that stretches back to their win over their arch-rivals in the Asian Cup final in 2011.
Japan coach Hajime Moriyasu says Thursday's match, albeit a dead rubber for his side, is a crucial part of his World Cup puzzle.
"Our main goal is to win the World Cup next year," Moriyasu said through an interpreter in Perth on Wednesday afternoon.
"And thinking about this ... we need to take each match seriously, step by step, and I think we need to build the strongest team possible towards the World Cup.
"It's true that the core member hasn't travelled to Australia this time, and you may think that it's not the best squad that we could possibly have.
"But I would like to show the world that we still have lots of players that are coming through, and I would like my players to shine on the very best stage tomorrow."
Socceroos coach Tony Popovic brushed off any concerns it would be challenging to prepare for some of Japan's lesser-known players.
"I'm sure in Japan's respect, they probably have 50 players to choose from that would all be worthy of representing their country," Popovic said.
"And we've played many games thus far where you don't know too much about a player that's been given a debut, someone that comes in that you don't know much about.
"There'll be a few of those for Japan, but we've been debuting players as well, and I'm sure they won't be too accustomed to some of the players that have played for Australia.
"It's not unique for us. We have a lot of respect for Japan. I know their coach very well. Fantastic person, done a wonderful job in qualifying.
"We want to join them automatically, and we have a chance to cement that further tomorrow."
