Richie Mo'unga, who retired with a sore shoulder in the second half of the All Blacks' 36-0 win over the Wallabies on August 17, has not been asked to play against the physical Tongans so close to the World Cup in Japan.
The absence of Mo'unga, who started the previous three tests at first-five, has resulted in the experienced Barrett shifting back to No 10 - where he has spent much of his test career - from fullback.
Ben Smith will start at fullback, and Ryan Crotty returns to the midfield after breaking his thumb playing for the Crusaders in the Super Rugby semifinal. This will be his first test of the year.
Smith's supporters will take great delight in him getting a start in the No 15 jersey, a position many believe suits him best.
He will also have plenty to prove after some lukewarm performances in the Rugby Championship. He struggled to get involved when he started on the right wing as All Blacks were trounced by the Wallabies in Perth on August 10, and was dropped for the Bledisloe Cup decider in Auckland a week later.
TJ Perenara has been rewarded with a start at halfback, with Aaron Smith on the bench. Hansen has resisted the temptation to give Brad Weber, the third halfback in the squad, a run on the ground where he was so impressive for the Chiefs during the Super Rugby season.
Once again there is no room for powerful Blues wing Rieko Ioane, who has not been listed in the match-day 23. Crusaders finishers Sevu Reece and George Bridge have been listed on the wings, having performed admirably against the Wallabies at Eden Park.
Their performances sealed their places in the 31-man World Cup squad that was revealed a week ago.
Uncapped first-five Josh Ioane, who will not travel to the World Cup because the selectors have decided to pick just two first-fives, has been listed on the bench as cover for the playmaker's position.
All Blacks coach Steve Hansen has made several changes to his forward pack, with Codie Taylor starting at hooker and Matt Todd getting a run at openside flanker.
Hansen has elected to keep Patrick Tuipulotu, who was impressive when he started in the win over the Wallabies, at lock. Scott Barrett, who missed the Bledisloe Cup encounter because of suspension, has been named on the bench after serving a three-week ban.
"It's great to get the squad together and start preparing for what will be a great match against Tonga. We know the Rugby World Cup is just around the corner, but we are focusing on 'right here, right now'," Hansen said.
"The players have brought real energy into our preparations here in Hamilton and the key will be to harness that excitement and put in a skillful and clinical performance on Saturday.
"Tonga will be targeting this game in a bid to build momentum into their Rugby World Cup campaign, and so are we, as it's going to be important for both teams to head into the tournament with confidence."
The All Blacks have played Tonga on five occasions - four of which have been in pool games at the World Cup. The last match between the sides was at the 2015 tournament. Five All Blacks from this weekend's squad - Sam Whitelock, Kieran Read, Aaron Smith, Ben Smith and Barrett - played that match.
This will be the All Blacks' final game before they depart for Japan on Monday. Their first pool game is against South Africa in Yokohama on September 21.
All Blacks: Ben Smith, Sevu Reece, Anton Lienert-Brown, Ryan Crotty, George Bridge, Beauden Barrett, TJ Perenara, Kieran Read (captain), Matt Todd, Ardie Savea, Sam Whitelock, Patrick Tuipulotu, Nepo Laulala, Codie Taylor, Joe Moody. Reserves: Liam Coltman, Ofa Tuungafasi, Angus Ta'avao, Scott Barrett, Luke Jacobson, Aaron Smith. Josh Ioane, Jordie Barrett.