"[Kicking coach] Mick [Byrne] and I both know what the issue is. It's just about trusting myself and staying in the process."
It was perhaps appropriate then that he joined former Pumas great Hugo Porta and back-up first-five Colin Slade in a sponsor-driven goalkicking display in the Argentine capital yesterday, although he remained extremely coy about the opportunity Cruden's slip-up has presented.
Barrett is obviously a major beneficiary of Cruden's two-test suspension, as is Slade to a lesser extent, but he is wary about getting ahead of himself.
"I'll find out if I'm next in line ... when the team is named, so we've just got to move on as a team," Barrett said.
Barrett was excellent apart from his kicking off the tee in Napier as he took advantage of Cruden's chest injury. His break set up Liam Messam's try after the halftime siren and his beautifully delayed pass sent Julian Savea through the defence.
His talent is undeniable, as is his ability to cover several positions and make an impact from the reserves bench. His test in difficult conditions in Napier - the rain started well before kick-off and never let up - proved he is a safe pair of hands from the start.
"Hopefully with the [fine] weather like it is at the moment ... we can play an expansive game. It can be noisy, we're aware of that," he said of the likely crowd involvement on Sunday. "Our communication has got to be world class."
Asked about Porta, a now 63-year-old who played 58 tests for Argentina, Barrett said: "I've definitely heard of him, it's great to meet the legend today. He could definitely kick a goal in his day."
Argentina have trimmed injured flanker Juan Manuel Leguizamon and hooker Santiago Iglesias Valdez from their 28-man squad.