Six Nations champions Ireland beat the Wallabies 26-21 in Melbourne last weekend to level the series at 1-1.
Australia can replace Wales in third spot in the rankings if they defeat Joe Schmidt’s side in the final Test at Allianz Stadium before it is demolished and rebuilt next year.
Captain Hooper is desperate to get his hands on the Lansdowne Trophy after what promises to be a gripping showdown.
“It’s certainly a big game. It’s going to be a great game. We’ve talked it up as a Grand Final. There’s a trophy on the line,” Hooper said.
“When we rolled into Sydney, it was a pretty low mood after that game last week in Melbourne,
“It takes you a while to re-energise and realise the position we are in tomorrow night, the occasion that it is, and how it’s going to be great for us and the fans alike.”
Captain's run ?? Ready for the decider
— Qantas Wallabies (@qantaswallabies) June 22, 2018
Hooper was encouraged by the threat Australia posed with ball in hand despite slipping to a defeat in the second Test.
“[There is] a lot of upside in that we can score points,” he added.
“Even right when the game is on the line we are able to put some nice attacking phases together. We looked at that [after the Melbourne Test] and thought that was really nice.
“In the negative of allowing them to control so much possession, you think if we changed a couple of things here we can get it back. We weren’t that far off what we needed to do.
“Ireland put together a good game and squeezed us really nicely with how they made us give away penalties.”
Australia can go third in the World Rugby rankings if they beat Ireland.
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