The fourteen South Africa players who flew to New Zealand on Thursday will be joined by another 22.
Head coach Steve Hansen says New Zealand's less-experienced players will learn from a huge battle with Argentina.
Argentina pushed New Zealand all the way in Buenos Aires, and All Blacks star Ardie Savea agreed the contest felt like war at times.
Argentina kept New Zealand scoreless for the second half of their Buenos Aires showdown, but could not avoid a Rugby Championship defeat.
Michael Hooper admitted Australia have a lot of things to work on following their 35-17 Rugby Championship defeat to South Africa.
South Africa debutant Herschel Jantjies did his World Cup chances no harm as he scored two tries in a dominant 35-17 win over Australia.
Former Ireland centre Brian O'Driscoll has heaped praise on coach Joe Schmidt and says Andy Farrell is the right man to replace him.
Australia endured a miserable 2018 and there is no room for error in a World Cup year. But can their mixed bag of a squad succeed?