Wynne Gray: Why the All Blacks have reason to worry about Pumas

Forget the backs, they'll be up for the battle with Argentina but there are significant questions about the All Black pack.

Only captain Kieran Read and Dane Coles carry regular test match authority and the onus will be on the others to combat the home side, conditions and unfamiliar surroundings.

Nepo Laulala is working strongly after a knee injury wrecked last season and Kane Hames remains a selectors' preference at loosehead prop without the same public acceptance because of his slim resume.

Luke Romano has the most test experience but does not start many matches and Scott Barrett is building well as a lock who is also capable of filling in on the blindside.

An outrageous try from Vaea Fifita masked some missing ingredients against the Boks while Matt Todd is well seasoned and consistent but a tick under top test level on the open side.

It's a patchwork quilt pack, looks alright at first glance but how does it stand up to serious scrutiny if the Pumas find some real cohesion. Getting the forwards sorted for this task on all levels will be priority for Steve Hansen and his coaching sidekicks.

Scrum, line out, ruck and maul, trust on defence, awareness around turnovers and tactical smarts will all be fed into the team data bank and the coaches' instincts during and after this test in Buenos Aires.

A win will seal the 2017 title and add to the depth of experience and trust the selectors want to build through the squad in the two years before the next World Cup.

Strong performances will bring reassurance about their ability to get on the international wavelength but glitches will narrow the concentration and open the options about the end of year tour to Europe.

Victory is the base line tomorrow and the All Black coaches have balanced that target with medical advice and their instincts about what's in the best interest of the squad. A tournament points lead affords them that selection shuffle and they'll all be judged on those alternate choices. Player depth can be a blessing and a headache but the All Blacks are using it as a poultice to bridge the excessive demands of a bloated professional calendar.