The All Blacks are three from three in 2015 but still they believe they've let themselves down with their start to the Rugby World Cup season, with Conrad Smith seeking higher standards across the board when the meet unbeaten Australia to fight out the Rugby Championship title in Sydney on Saturday.

Smith is none too pleased with the world champions' form in wins over Samoa, Argentina and South Africa, with New Zealand having been out-muscled in the second half in Apia and patchy for periods against the Pumas; and despite the good press after their 27-20 win over South Africa at Ellis Park, the veteran centre said there were plenty of dropped heads during the review process.

"All Blacks sides are good at looking past results and at performance," Smith said. "If anything, we've been critical of the way we played in Johannesburg because there was a lot that we didn't do right. It is a tough place to win so we've accepted that and there was a pat on the back. The rest of it was a pat on the backside probably."

The 86-cap veteran produced a mixed bag in his first Test of the year, spilling a simple ball on attack and seeing Springboks centre Jessie Kriel carve between him and midfield partner Ma'a Nonu to score in the second half.

Nonu is unlikely to play because of his shoulder injury, despite training lightly this week, and Smith says he will make it his priority to jell properly with whoever starts at second five-eighth to ensure there is no repeat of his performance in South Africa.

"For myself, I was a step off the pace in South Africa," Smith said. "I'd like to obviously build a relationship with the guy I'm alongside. And as a backline, I'm sure we'd like to create a few more opportunities and then take them. That's something we haven't done in the Tests so far."

Sonny Bill Williams is favoured to wear the No.12 jumper in what would be his 26th Test, but just his second on Australian soil.

Smith believes Williams can handle the intensity of playing in Sydney, where he has a high profile and his fair share of critics following roller-coaster NRL stints there.

"He's used to it, I'm sure. He attracts attention wherever he goes. If anything, I think he enjoys it and draws a lot of motivation from it."