Speaking on the Rugby Rivals podcast, Kirwan pointed to Dave Rennie's latest squad selection.

"Richie Mo'unga's carrying a bit of an injury but they're taking him anyway, so that tells you a bit of a sign," he said.

Kirwan then made his feelings on Barrett clear.

"Beauden Barrett's definitely a full-back so we can forget about him at 10."

Barrett has spent much of his international career at fly-half, but Kirwan believes his future now lies elsewhere.

Rennie has also named the veteran among his outside backs for November.

That leaves Damian McKenzie, Richie Mo'unga and uncapped Josh Jacomb as New Zealand's main options at fly-half.

All Blacks face major selection decisions

New Zealand face Scotland, Wales and England on consecutive weekends during the Nations Championship.

The matches offer Rennie another opportunity to settle his preferred combinations ahead of the 2027 Rugby World Cup.

Kirwan also questioned Rieko Ioane's classification as an outside back rather than a centre.

"They've named Rieko Ioane as an outside back rather than a centre which I thought was interesting," he said.

With competition increasing across the backline, Barrett's future at fly-half now looks increasingly uncertain.

Pick your All Blacks XV

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