Tokyo - All Blacks coach Steve Hansen has made it clear expects rookie flyhalf and rising star Jordie Barrett to boss the team against Namibia on Sunday, and he's not to be overruled by more seasoned players.

Jordie, 22, has played most of his 13 Tests at fullback or wing and Hansen raised eyebrows when he named the utility to wear the 10 jersey for the first time in their penultimate Pool B match.

He is one of only three players retained from the starting line-up against Canada on Wednesday with the new-look side including the return of Brodie Retallick, who has been sidelined with a dislocated shoulder for 10 weeks, while Ben Smith is restored at fullback.

The 88-Test veteran Aaron Smith will start at scrum-half but he has been given the message that Jordie Barrett is in charge.

Jordie, the youngest of the All Blacks' three Barrett brothers, who has watched his eldest sibling - and double World Player of the Year - Beauden fill the pivot position for several years, had no hesitation in taking on the new role at short notice.

The decision to rest twin playmakers Beauden Barrett and Richie Mo'unga was only taken after the All Blacks came through Wednesday's 63-0 romp against Canada unscathed.

"I guess there will have to be a few adjustments that I will have to make," Jordie Barrett said of his limited time to prepare.

"But within our structure the number 15 often performs the 10 role within our phase play, so it is more just set-piece, and little things, and timings that I will have to equip myself (with) over the next 48 hours."

Hansen, who has been urging the youngest Barrett to tone down his exuberance in training, was in no doubt he would slot in easily at fly-half, but it should not be seen as a permanent move.

"He's got plenty of swagger, anyone who has seen him knows that. He'll boss the game. But swagger and confidence shouldn't be confused with arrogance," Hansen said.

"Hopefully we don't see him at 10 too many times. He's a back-three player. As he gets older he may end up in midfield. He has a big boot, he's good under the high ball. He's brave with chase and catch, good handling skills."

Hansen said he had emphasised to Aaron Smith and back-up scrumhalf Brad Weber that the novice 10 Jordie was in charge.

"I told them that he (Barrett) is the boss. They need to listen to him, not the other way round. Number 10 is always your main computer. When nine starts making the choice you end up getting chaos."

The All Blacks have included all of their three scrumhalves in the match-day 23 with TJ Perenara on the bench as back up to Jordie Barrett.

Sam Whitelock, who will captain the side in the absence of Kieran Read who is being rested, gave his endorsement to Jordie Barrett saying he was "in a pretty awesome position and he's pretty clued up on how he wants this team to play".

The All Blacks, with only Italy to play in pool matches after Namibia, are considered the tournament frontrunners, and Hansen is happy to have it that way.

"I'd rather have the favourite in a horse race than an outsider. The favourite often wins. I'm not saying we will win it, we need to earn that... but I would rather come here and hear that we're the favourites, than to hear we have no chance."

Teams:

New Zealand

15 Ben Smith, 14 Sevu Reece, 13 Jack Goodhue, 12 Anton Lienert-Brown, 11 George Bridge, 10 Jordie Barrett, 9 Aaron Smith, 8 Ardie Savea, 7 Sam Cane, 6 Shannon Frizell, 5 Sam Whitelock (captain), 4 Brodie Retallick, 3 Nepo Laulala, 2 Codie Taylor, 1 Joe Moody

Substitutes: 16 Dane Coles, 17 Ofa Tu'ungafasi, 18 Angus Ta'avao, 19 Patrick Tuipulotu, 20 Matt Todd, 21 Brad Weber, 22 TJ Perenara, 23 Rieko Ioane

Namibia

15 Johan Tromp, 14. Lesley Klim, 13 Justin Newman, 12 Johan Deysel (captain), 11 JC Greyling, 10 Helarius Axasman Kisting, 9 Damian Stevens, 8 Janco Venter, 7 Thomasau Forbes, 6 Prince Gaoseb, 5 Tjiuee Uanivi, 4 PJ van Lill, 3 AJ de Klerk, 2 Torsten van Jaarsveld, 1 Andre Rademeyer

Substitutes: 16 Obert Nortje, 17 Nelius Theron, 18 Johannes Coetzee, 19 Johan Retief, 20 Adriaan Booysen, 21 Eugene Jantjies, 22 Darryl de la Harpe, 23 Janry du Toit