When he kept it throughout September and October, it was largely due to Cruden being in the dog house for missing a flight to Argentina.
And when he wore it in the third test this June against Wales, again, it was because Cruden wasn't available due to injury.
But tomorrow, Barrett will run out at ANZ Stadium knowing that he's not benefiting from another's misfortune. He has won the right to start because he has played consistently excellent rugby for the past two months.
He is the man the All Blacks believe is best placed to drive the team; to give them the direction and control they will need.
"In the end, it was pretty easy," said All Blacks coach Steve Hansen about having to decide whether to start Barrett or Cruden against the Wallabies. "Beauden's performances over the last month have been outstanding, both for the All Blacks and for the Hurricanes, and he has just got to be on the park for 80 minutes."
The difference between Barrett now and a year ago is the composure and authority he brings to the role. The All Blacks need a tactical dictator as much, if not more, than they need game-breaking wizardry and it has been the growth of Barrett in the former that has impressed Hansen.
"Probably his game management really," offered the All Blacks coach in regard to what had pushed Barrett into the starting role. "He has been able to control the games and we saw that on the big occasions -- in the quarters, semis and final of Super Rugby. In really trying conditions, he controlled the tempo of the games.
"His kicking game was good, his running game was excellent. He has just matured and he's getting better all the time."
Barrett felt that a variety of factors had helped him build his portfolio this year. Some of it, he said, would be down to simply being a year older and wiser. Experience, especially for a No 10, is critical in building game awareness and understanding. To some extent, he proved that by his performances in Super Rugby's knockout rounds, especially the final.
In 2015, he didn't play the way he wanted in the final. He was quiet, made a few mistakes and lost some confidence. Having experienced that once, he bounced back in 2016 with a man of the match performance against the Lions.
He also attributes some of his improved form this year to having taken up pilates and yoga. A brilliant but not particularly flexible athlete, Barrett has given himself a better range of movement through extracurricular work.
"I am always looking to grow my game and I still have a lot of growth to do," he said. "The key thing is that I am enjoying my footy at the moment. I'm just in a better head space.
"There are other physical things but I think if you get your head right and your approach to the game, that balance is crucial. I have been working on my flexibility and that has been vital for me.
"I am quite a stiff bloke, so extra sessions here and there have certainly helped. Yoga and pilates have really helped. It is more a recovery thing for me and it is great for the mind as well as the body, and I have seen great benefits from it."
