Australia take on Argentina on Saturday with new skipper Nathan Sharpe at the helm amid a captaincy crisis as they seek to build on their first win in the Rugby Championship.
After two defeats to world champions New Zealand to open their campaign, the Wallabies came from behind to beat the Springboks last week, giving under-siege coach Robbie Deans much-needed breathing space.
But the 26-19 win in Perth came at a cost with skipper Will Genia badly injuring his knee. First-choice captain James Horwill is also sidelined, along with his successor David Pocock.
The Wallabies start as favourites for the Gold Coast clash but will be wary of a Pumas outfit that pushed the All Blacks hard for 60 minutes last weekend before eventually fading to lose 21-5.
Australia insist they will not underestimate the Argentinians, who held the Springboks to a 16-16 draw in Mendoza last month in the inaugural championship.
Sharpe, 34, who originally announced he was going to retire earlier this year, is the only Australian player to have faced the Pumas, and flyhalf Quade Cooper admitted the Wallabies had little knowledge of the South Americans.
"There's been a lot of tape-watching this week for a lot of the boys," Cooper said.
"We don't know much about them and no one in the team, except for Sharpey, has had the opportunity to play against them.
"Their unpredictability is a big strength... and also their forward pack. They're definitely a team we're not taking lightly at all. They're going to throw a lot at us."
The enigmatic Cooper will be faced with extra responsibility following the season-ending knee injury to scrumhalf Genia last week.
Melbourne's Nick Phipps comes into the side at scrumhalf in one of three changes to the Wallabies team from the Springboks match.
Waratahs lock Kane Douglas will make his Test debut in place of injured Sitaleki Timani, while inside centre Pat McCabe returns from injury, with Berrick Barnes dropping to fullback and Kurtley Beale to the bench.
Sharpe, who had intended to retire at the end of the Super 15 season before an injury to Horwill led to his call-up, takes over from Genia as captain. He has captained Australia twice before.
Argentina's Leicester-based front-rower Marcos Ayerza, who is in the Pumas squad but will not be playing Saturday, said Genia's injury would be a huge loss for the Wallabies.
"When you lose a key player like a number nine or ten, a captain, it makes a large difference and we hope to use that to our advantage," he said.
"It's a huge task for us to compete with Australia. We are desperate to get our first win and we know that if we are not at 110 per cent that will not happen."
Pumas coach Santiago Phelan has made two backline changes to the team that lost to the All Blacks, dropping scrumhalf Nicolas Vergallo and fullback Martin Rodriguez.
Martin Landajo comes in for Vergallo, while the exciting Lucas Gonzalez Amorosino takes over at fullback.