Leicester - Argentina overhauled their side in anticipation of facing Namibia on Sunday having already qualified for the Rugby World Cup quarter-finals.
If New Zealand beat Tonga as expected in Newcastle late on Friday, the Pumas will qualify for the last eight from Pool C for a third successive World Cup.
The Pumas are also heavily favoured against the Namibians, who are still seeking their first win at their fifth Rugby World Cup.
Argentina and Namibia both made 11 changes for Sunday's match.
From the starting lineup in the 45-16 win over Tonga last Sunday in Leicester, the Pumas retained only lock Guido Petti, flank Pablo Matera, scrumhalf Martin Landajo, who will be captain, and wing Matias Moroni.
Two backs, flyhalf Juan Martin Hernandez and wing Horacio Agulla share 115 caps, almost a third of the 349 total.
It is the youngest and most inexperienced Pumas line-up at a Rugby World Cup in 16 years, and the start for centre Juan Pablo Socino ensures every Puma in the squad will have played at least once in the pool stage.
Namibia, affected by a four-day turnaround after losing to Georgia 17-16 on Wednesday in Exeter, have given successive starts to only hooker Torsten van Jaarsveld, lock Tjiuee Uanivi, flyhalf Theuns Kotze, and fullback Chrysander Botha.
Uanivi and Kotze have played all 240 minutes of Namibia's campaign so far.
Flank Jacques Burger retired after he was concussed against Georgia, and the captaincy was passed to flank Rohan Kitshoff, who was usually the skipper between World Cups.
15 Lucas Gonzalez Amorosino, 14 Matias Moroni, 13 Santiago Gonzalez Iglesias, 12 Juan Pablo Socino, 11 Horacio Agulla, 10 Juan Martin Hernandez, 9 Martin Landajo (captain), 8 Facundo Isa, 7 Javier Ortega Desio, 6 Pablo Matera, 5 Matias Alemanno, 4 Guido Petti, 3 Juan Pablo Orlandi, 2 Julian Montoya, 1. Lucas Noguera
Substitutes: 16 Agustin Creevy, 17 Marcos Ayerza, 18 Ramiro Herrera, 19. Leonardo Senatore, 20 Juan Martin Fernandez Lobbe, 21 Tomas Cubelli, 22 Marcelo Bosch, 23 Juan Imhoff
15 Chrysander Botha, 14 Johan Tromp, 13 JC Greyling, 12 Johan Deysel, 11 Conrad Marais, 10 Theuns Kotze, 9 Eneill Buitendag, 8 Leneve Damens, 7 Wian Conradie, 6 Rohan Kitsoff (captain), 5 Tijuee Uanivi, 4 Janco Venter, 3 Johannes Coetzee, 2 Torsten Van Jaarsveld, 1 Jaco Engels
Substitutes: 16 Louis van der Westhuizen, 17 Johnny Redelinghuys, 18 Raoul Larson, 19 Renaldo Bothma, 20 Tinus Du Plessis, 21 PJ Van Lill, 22 Eugene Jantjes, 23 Heinrich Smit