Carter's virtuoso performance in Saturday's 35-17 win over South Africa in which he kicked 25 points and played key roles in both All Blacks tries at Wellington was noted by the Wallabies.
His rival in the first five-eighths position Stephen Larkham told the Sydney Morning Herald, "He had a big game, just as he did at the same venue against the Lions.
"So he's in good form at the moment, he's looking very comfortable and he's going to make it difficult.
"When you've got someone so confident who's running the game well, the whole team will play with a lot of confidence."
The Australians also noted Carter's comments that he, and the All Blacks, preferred playing the more open style of games that occur against the Wallabies.
However, since the All Blacks beat Australia in the opening Tri Nations game in Christchurch, Matt Giteau has returned to the midfield and his fitness has been improving with every outing.
"I think he's spent a lot of time since the operation on his knee getting fitness back, and a lot of that work has involved speed work, and that's definitely showing at the moment.
"He's certainly the quickest I've ever seen him since I've played with him. Off the mark and top speed, he's very sharp at the moment," Larkham said of his former Brumbies teammate.
But the All Blacks forwards are expecting a tougher task fronting up to the Australian pack.
Prop Greg Somerville said scrums change from week to week and the All Blacks had their feet well and truly on the ground.
"There could be different people out there and it will be totally different," he told AAP.
Somerville added that the Wallabies also had ways of reducing the importance of the scrum by employing other options.