Coach Hansen named three hookers for the tour, with Bay of Plenty rake Harris joining Dane Coles and veteran Keven Mealamu in the 31-man squad for the matches in La Plata on Sept.
27 and Johannesburg on Oct. 4.
Harris, who has been part of the wider training squad this year, is likely to make his debut off the bench in Johannesburg as Coles will return to New Zealand following the Argentina test to attend the birth of his first child.
Utility back Ryan Crotty has also been named in the squad but only for the South Africa leg as he has just made his return for Canterbury in provincial rugby after breaking his cheekbone.
Crotty’s absence from Argentina almost certainly ensures Malakai Fekitoa of a start at inside centre alongside the other specialist centre in the squad, Conrad Smith, although Ben Smith and Charles Piutau can both play in the midfield if required.
Ben Smith played inside centre for the second half of the All Blacks’ 14-10 victory over South Africa in Wellington last Saturday in place of the injured Ma’a Nonu, who has been ruled out for the year after breaking his arm in the game.
Injured flyhalf Dan Carter as well as locks Patrick Tuipulotu and Dominic Bird have been released from the squad and will play provincial rugby to get back to match fitness following injuries.
Lock Sam Whitelock and loose forwards Jerome Kaino and Liam Messam, though, have all recovered from their injuries and will be on the plane to Argentina at the weekend.
Forwards: #Dane Coles, Nathan Harris, Keven Mealamu, Wyatt Crockett, Charlie Faumuina, Ben Franks, Owen Franks, Joe Moody, Brodie Retallick, Jeremy Thrush, Sam Whitelock, Sam Cane, Jerome Kaino, Steven Luatua, Richie McCaw, Liam Messam, Kieran Read.
Backs: Tawera Kerr-Barlow, TJ Perenara, Aaron Smith, Aaron Cruden, Beauden Barrett, Colin Slade, *Ryan Crotty, Conrad Smith, Malakai Fekitoa, Israel Dagg, Cory Jane, Charles Piutau, Julian Savea, Ben Smith.
# only for Argentina leg; * only for South Africa leg
(Reporting by Greg Stutchbury; Editing by Nick Mulvenney)