The Wallabies have won four of their five previous tests against the men in blue, but the Manu prevailed 32-23 when the teams last played eight years ago.
Head coach Steve Jackson said games like this don't come around very often and his players are feeling extremely confident.
"This is about our 2019 and what these players can go out and do against Australia and create their own little piece of history and this game is hugely important to us.
"We know we talk about Rugby World Cup but this occasion it's a test match against Australia in Sydney and they don't come any better than that. These guys are excited, they've been talking about it all week and they've just got to go out there and believe in themselves. We're not going out there to make up numbers, we're going out there because we believe that we can win."
Australia have rested a number of front-line players for this weekend's match, including prop Allan Alaalatoa, who missed the chance to play against his older brother Michael on test debut.
But Steve Jackson isn't buying talk of a weak Wallabies team.
"They've got David Pocock who's come back but is arguably is one of the best loose forwards in the world and then you've got (Sekope) Kepu who is retiring - this will be his last game here in Australia before he retires after Rugby World Cup, so there's a bit of emotion there for them moving into this game as well.
"There's obviously a couple of guys in their team that are getting their opportunity to play as well so we don't take these guys lightly. I know the media has been saying it's a second-string Australian side but we don't believe that at any point. It's a strong Australian team we're going to be facing."
The Manu Samoa squad will fly back to Auckland on Monday before departing from Japan the following morning.