Aaron Smith has broken team protocol and has been relegated to the reserves for the All Blacks' Rugby Championship Test against South Africa in Dunedin on Saturday night.
Smith had started at halfback in all six previous Tests this season and his indiscretion gives Piri Weepu his first start since last year's Rugby World Cup.
All Blacks' coach Steve Hansen made no apology for the decision to demote Smith.
He said there was a strong focus on recovery after Test matches and Smith had breached protocol after the match against Argentina in Wellington last weekend.
"Protocols are non-negotiable and the consequences are you don't start in the playing 15 if you break them."
Hansen said it was irrelevant to speculate whether Smith would have started had he not broken protocol.
"He broke them so we don't need to go there. The other fellow (Weepu) played pretty well last weekend as well. We're very fortunate we've got two good halfbacks."
Hansen declined to specify Smith's offence but replied "no" when asked whether alcohol was a factor.
The return of Weepu, who will be playing his 63rd Test, is one of four changes to the All Blacks' starting lineup.
The others are in the forwards where Liam Messam slots in at blindside flanker in place of Victor Vito, lock Sam Whitelock comes in for Brodie Retallick and Andrew Hore starts at hooker instead of Keven Mealamu.
There is also a change in the back reserves where Highlander Tamati Ellison replaces teammate Ben Smith because of his ability to cover second five-eighth in the absence of Dan Carter.
Hansen said Messam had demanded selection with his form for the Chiefs and All Blacks this season.
"Liam's comfortable in his own skin and he's playing particularly well. He brings a consistency of high quality performance and just a little more physicality than Victor."
Whitelock had responded well to his demotion last week and Retallick, in his first season of All Blacks rugby, needed to be managed well through the campaign.
"Brodie doesn't necessarily need to start every Test at this stage of his career and he's still got a lot of rugby ahead of him this season."
Hansen said there was little between Hore and Mealamu at hooker and either could have started.
All Blacks:Israel Dagg, Cory Jane, Conrad Smith, Ma'a Nonu, Julian Savea, Aaron Cruden, Piri Weepu, Kieran Read, Richie McCaw (captain), Liam Messam, Sam Whitelock, Luke Romano, Owen Franks, Andrew Hore, Tony Woodcock. Reserves: Tamati Ellison, Beauden Barrett, Aaron Smith, Victor Vito, Brodie Retallick, Charlie Faumuina, Keven Mealamu.