All Blacks assistant coach Scott Hansen said Barrett will be close to the team, and the medical staff will do everything to have him ready as soon as possible.
Hansen said the team for the first Test against Argentina will be the group the selectors feel can give them the game they need.
With Sam Cane's return to the squad, leadership will not be lacking. While with the side in its preparation for England and Fiji, he was a significant influence on its leadership standards and quality of control.
Beauden Barrett was another whose influence was significant within the group.
"The way he's led our weeks, the clarity, composure, whether that be at 10 or fullbacks. The influence he's had on this group has been massive in the last three Tests."
A feature of the squad is the choice of halfbacks Cortez Ratima and Noah Hotham to join TJ Perenara as contenders for the starting role.
Hansen said Hotham's running game was a point of difference, and he earned his opportunity after showing the ability to change the All Blacks' point of attack against Fiji.
He and Ratima, who Hotham replaced against Fiji, thrived in the All Blacks environment.
"He's [Ratima] a great young man open to learning, listening and growing his game. We're excited by the nines [halfbacks] we have in the country.
"We've got Finlay [Calder] at home at the moment, and then you've got Folau [Fakatava] also."
TJ Perenara is ready to play again and will turn out in a game for Wellington this week.
Hansen said a running halfback could change the opposition's defence approach with their instincts.
That skill was backed by the balance around their game, their game management and ability to create contestable ball through their kicks.
Cam Roigard's recovery is progressing well, and he has been part of the team in Wellington. He is absorbing the game the coaches are looking to play, and as a player with a lot of rugby in his future, they are doing what is best for him.
"We know after looking at Super Rugby, the influence he had in the early rounds was phenomenal. We've got to look after him and make sure when he comes back he's comfortable and confident."
Will Jordan is still seen as a player who can play fullback and wing.
"When you talk about the All Black outside backs, our strength has always been their ability to cover fullback or wing.
"Will Jordan is a world-class athlete and rugby player. That gives us the ability to play him at fullback, where he's been selected, but also, our memory allows us to look at where he was last year on the right wing for the All Blacks.
"We're lucky to have the ability to use Will where we need to."
Jordan will play with Tasman, but Hansen said he was involved with the All Blacks during the England series, where there was contact conditioning and he was put in positions where he would be challenged in areas of the game.
"He's been leading into that for the last number of weeks. He is a player that can come out and play Test match footy straight away."
Ruben Love is another player who worked with the squad during the England series.
"He's had a fantastic Super campaign. He was with us for a number of weeks leading into the series and we saw a lot of really good attributes around him learning his craft, being professional, running well as the opposition. He gave us a lot during our week."
Emoni Narawa missed the squad but needed to play rugby and score tries to regain his flow.