Although the trophy cabinet is already full All Blacks assistant coach Ian Foster is not worried about his side lacking motivation this weekend.

The world champions may have already secured the Bledisloe Cup, but Foster is not concerned about their performance levels dropping off in Brisbane on Saturday as they look to continue their unbeaten run.

Foster said that their comprehensive victory over the Springboks in Soweto showed that his team is motivated by more than just silverware.

He told Fairfax media: "I think we showed in the Soweto game how much it means to this team just to perform on the day and to put our best foot forward.

"This Bledisloe Cup game is the same equation. There will be some people say that we have already won it and maybe we can loosen up a wee bit but the reality is we just want to keep performing.

"We're in good preparation routines at the moment; the team has taken grasp of that responsibility, and is doing a great job. There's no need to slacken off on it," he added.

Foster has taken a more central role in the build-up to the Test match as head coach Steve Hansen has had to spend time with his father who is seriously ill.

The former Chiefs boss said that although the All Blacks have not lost to the Wallabies since before the World Cup last year, they are expecting a stern test in Brisbane against an Australian team that has come through their injury crisis quite well.

"Australia are an arch rival. While there has been a lot said about them this year, they have had a few injuries, they have still come out with a 3-3 record in the Rugby Championship which is not to be sneezed at.

"If you go back to our two games, in both we perhaps missed a lot of opportunities to put points on them.

"But I think that was largely due to the tenacity of their defence and their attitude. While I think we are probably a little better than those days, their attitude and their desire to play well against us is going to guarantee that this is a very tough game," he said.

Foster explained that the All Blacks are determined to set the record straight at Suncorp Stadium which is the venue of their last Test defeat.

"Historically the Aussies have played very well in Brisbane. The last time the All Blacks lost was there and history is full of times that the Australians have seemingly been down and out and they've shown a massive amount of character and played really well against us under that sort of pressure.

"We are fully aware that a really strong performance from them can certainly change the whole perception of their season. They'd love to have our scalp, so there's plenty to play for," he said.