The Brumbies' big man was almost flawless in the Wallabies' 47-26 shock win over the All Blacks in their Bledisloe Cup clash in Perth.

As well as anchoring the lineout, Arnold had a try-assist and a couple of tackle busts as the Wallabies' tight-five excelled.

Former Wallabies skipper turned television commentator Phil Kearns said Arnold was "up there alongside Retallick", who is known for his pace and try-scoring efforts as well as his set-piece work.

Before the return clash in Auckland on Saturday which will decide the Bledisloe Cup, 29-year-old Arnold wasn't so sure.

"Maybe Phil's hamming up that with those comments," he said on Monday.

"I don't think I'm doing a hell of a lot different to the last few years; I'm just enjoying my footy."

Signed to join his brother Richie at French club Toulouse after the World Cup, Arnold said he was determined to make his last hurrah in a gold jersey count.

"Maybe it's the fact that I'm heading overseas and this is my last season in (the) Wallabies, I'm not sure," he said.

"I just want to keep building and keep moving forward."

Retallick is currently sidelined after dislocating his shoulder last month against South Africa, with the injury threatening his World Cup campaign.

The All Blacks also face a nervous wait on the outcome of a SANZAAR judiciary hearing after lock Scott Barrett was sent off in Perth.

Barrett could face up to six weeks out for a no-arm tackle that collected the head of Wallabies skipper Michael Hooper.

Barrett had replaced Retallick, with the All Blacks depth falling away with Patrick Tuipulotu or Jackson Hemopo possibilities to come in and partner Sam Whitelock.

Arnold believed they would still be a force and said the Wallabies wouldn't be targeting the All Blacks lineout as a weakness.

"They've got a lot of good depth there in New Zealand," he said.

"I'm sure the next bloke that comes in for those fellas will be just as good as what they are.

"I think it's going to be a very close contest."

The Wallabies have started a low-key Bledisloe build-up in Melbourne rather than flying to Auckland.

They are trying to break through for their first win at Eden Park since 1986 which would secure the trans-Tasman trophy which has been in Kiwi hands since 2003.

Arnold said the Wallabies would need to lift, just as the All Blacks always did at their spiritual home.

"Historically it's obviously a hard place for the Wallabies to win and I can't remember the last time," he said.

"I've only played there once. It was pretty intense. The crowd's pretty hostile.

"They just seem to lift whenever they play (there) and that's the challenge that awaits us this weekend."

Australian Associated Press