All Blacks coach Graham Henry says he would have been throwing former NRL superstar Sonny Bill Williams into the deep end by playing him in Saturday's Bledisloe Cup Test against Australia.

Williams has missed out on the chance of a Test debut in the 15-man game in the first match of New Zealand's five-Test spring tour, not named among the 22 for the Hong Kong Stadium showdown.

The 25-year-old had been tipped as a possible bench man after the All Blacks fast-tracked him into their touring squad.

"We didn't want to fire Sonny Bill in the deep end," Henry told reporters on Thursday.

"We think he needs a wee bit of time to get accustomed to what we're trying to do out there.

"I think it would have been a big ask to throw him out there in a big Test match like this without having time to get his feet under the table.

"Also, we're delighted with what (starting centres) Ma'a Nonu and Conrad Smith have done for this All Black team over the last 12 months."

Saturday's fourth Bledisloe encounter is crucial to both sides' confidence heading into next year's Rugby World Cup but, with the All Blacks having wrapped up the series 3-0 already, would also have been an opportunity to blood Williams.

Henry was coy about when or whether the giant former Canterbury Bulldogs centre will get a run in the grand slam Tests on tour.

"It takes a wee little while to get clarity on what the team's trying to do, so give it time to understand the team game-plan, the team culture and what we're trying to do out there, and that's natural," Henry said.

"It's just going to take time for those (new) guys to understand what we're trying to do and feel comfortable with that so they're not cluttered.

"So they'll get better as the tour goes on because they'll have more knowledge and therefore will be better equipped to play Test match football, whether it be next week or the week after or whenever it may be.

"So time in the group is very important."

Champion five-eighth Dan Carter is among four changes to the All Blacks side that beat the Wallabies 23-22 last month.

Carter is returning after surgery to remove floating bone fragments from his right ankle.

Former Queensland forward Daniel Braid will play his first Test since 2008.

New Zealand: Mils Muliaina, Cory Jane, Conrad Smith, Ma'a Nonu, Josevata Rokocoko, Daniel Carter, Jimmy Cowan, Kieran Read, Richie McCaw (capt), Jerome Kaino, Tom Donnelly, Brad Thorn, Owen Franks, Keven Mealamu, Tony Woodcock. Res: Hikawera Elliot, John Afoa, Samuel Whitelock, Daniel Braid, Alby Mathewson, Stephen Donald, Isaia Toeava.

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