Scott Barrett goes under the knife upon return to New Zealand

All Blacks captain Scott Barrett is the latest question mark in Scott Robertson's Rugby Championship squad, having required surgery on a finger injury sustained against Fiji in San Diego.

A statement from New Zealand Rugby on Saturday revealed the injury without offering a timeline for recovery.

"Scott Barrett injured a finger during the All Blacks Test against Fiji in San Diego which has required a surgical treatment after return to New Zealand," the statement read.

"The injury is now being assessed."

It is expected the coaching group will provide more insight following The Rugby Championship squad naming on Sunday.

The squad will need a new captain should Barrett miss game time in the opening Tests against Argentina in two weeks' time, with additional second-row cover also required.

The team opted to select just three locks in the Steinlager Series squad, with Barrett joined by Patrick Tuipulotu and Tupou Vaa'i, with the former's health a question mark in itself.

Tuipulotu made a miraculous return to the fold after injuring his MCL in the Super Rugby Pacific quarter-final against Fiji, only to play two weeks later in the grand final.

While it was an incredible feat, the Blues captain was absent from the trip to California as medics decided it was best to rest and recover some more after a gruelling England series.

It leaves Vaa'i as the lone healthy lock from the 33-man squad.

24-year-old Sam Darry took Tuipulotu's place in San Diego, making his All Blacks debut as the first in a new era of second rowers following the iconic careers of Sam Whitelock and Brodie Retallick in the black jersey.

Darry was joined by four-time All Black Josh Lord in All Blacks camp throughout the England series as additional cover, and selectors may call upon both players once more for The Rugby Championship.

The team will also need a captain. Vice-captain and reigning World Rugby Player of the Year Ardie Savea is considered the leading contender for the honour, one which he has shared eight times previously.