Phipps will step up to the number nine jersey to replace Wallabies skipper Will Genia who has suffered a season-ending knee injury.
The Pumas have made no secret that they see Phipps as Australia's weak link and that their chances of an upset victory have been boosted by Genia's long-term absence.
Argentina have been surprisingly competitive in the first three matches in the expanded tournament and they are desperate for a first scalp.
While the Pumas have drawn with South Africa and rattled the All Blacks for an hour in a 21-5 loss in Wellington, the Wallabies have struggled to go close to their best and were far from convincing 26-19 winners over the Springboks on Saturday in Perth where Genia was hurt.
The Pumas are in no doubt how much the Wallabies will miss Genia.
"Massively. I think he's been a talisman for them," veteran Pumas prop Marcos Ayerza said.
"He's a very important player for them.
"To lose a key player like a number nine or 10 ... and a captain ... is a massive loss for Australia and hopefully we can use that to our advantage."
Pumas coach Santiago Phelan has dropped half-back Nicolas Vergallo and full-back Martin Rodriguez, replacing them with Martin Landajo and Lucas Gonzalez Amorosino.
Vice-captain Patricio Albacete, a stand-out in the Argentinian second-row, will earn his 50th cap, lining up opposite Wallabies veteran Nathan Sharpe, who will skipper Australia in his 109th Test.
The Argentina team is: Amorosino; Camacho, Bosch, Fernandez, Agulla; Hernandez, Landajo; Roncero, Guinazu, Figallo, Carizza, Albacete, Cabello, Leguizamon, Fernandez Lobbe (captain).