All Blacks prop Joe Moody has been ruled out for the rest of the year after dislocating his shoulder in Saturday's 39-22 victory over Argentina in the Rugby Championship.
Moody's injury is a further test of coach Steve Hansen's front row depth, with first-choice tighthead prop Owen Franks also ruled out for the rest of the season due to surgery on his Achilles tendon.
Charlie Faumuina, who carved out most of his international career coming off the bench to replace Franks, also left for a contract in France after Super Rugby ended.
Moody, whose scrummaging against Nahuel Tetaz Chaparro had put the Pumas under immense pressure, left the field at Taranaki Regional Stadium in the 64th minute in obvious pain with his right arm supported in a makeshift sling.
"He'll need an operation and is probably going to need six months out," Hansen told reporters in New Plymouth.
The All Blacks have recalled Kane Hames, who was brought in as cover for the second test against Australia two weeks ago after Wyatt Crockett was concussed.
Crockett is expected to move into the starting position, with Hames, whose two tests have been off the bench against Australia, likely to be among the replacements for the clash with South Africa in Auckland on Saturday.
After Canterbury Crusaders veteran Crockett and Hames, there is a dearth of potential contenders at loosehead.
Nepo Laulala, who made his debut in 2015 before spending all of 2016 injured, has returned and impressed with his solid scrummaging as the starting tighthead in place of Franks.
Ofa Tu'ungafasi made his All Blacks debut last year and is being groomed as someone who can play both sides of the scrum but he has made six of his seven test appearaces as the specialist tighthead replacement.
Hansen named uncapped loosehead Atu Moli as an 'apprentice' player for the Rugby Championship and he said the injuries meant he would probably need to introduce more new faces.
"We can either sit here and sulk about that or we can say this is an opportunity for us to have to grow some talent and give people opportunites," Hansen added.
"In the past people have stood up. We will need them to."