Gold Coast - Wallabies skipper Nathan Sharpe on Friday warned his team against complacency when they face Argentina, which he warned was a spirited and passionate side.
Australia face the Pumas at the Gold Coast on Saturday, hoping to build on their 26-19 win against South Africa last week.
But Sharpe is wary of their opponents after watching them push the All Blacks hard for 60 minutes last weekend before eventually fading to lose 21-5. They also held the Springboks to a 16-16 draw in Mendoza last month.
"The main memory I do have is the unorthodox method in which they play," said Sharpe, the only player in the Australian squad to have faced Argentina before, in 2003.
"They're a very passionate team and it's something that's been identified in the first games of the Rugby Championship and one that you look at in every Rugby World Cup, they're always competitive due to that spirit.
"The thing about them as a team is they play well as a team," added Sharpe, who is at the helm after previous skipper Will Genia badly injured his knee last weekend.
"They don't generally have a consistent stand-out, they just perform well and put in for each other and that's what makes them a dangerous team.
"You talk about their defence and all the rest of it, it's not always the most structured but it's frenetic."
The tourists, advised by former New Zealand coach Graham Henry, are desperate to score an historic tournament win - which would also be their first triumph on Australian soil in 29 years.
Despite being the underdogs, Argentina believe the injury-plagued Australia are vulnerable without halfback Genia and Perth man-of-the-match Sitaleki Timani.
But Sharpe expects replacements Nick Phipps and Kane Douglas and the rest of his team to respond.
"It's good for the team because people have to step up," he said.
"When you are faced with a situation generally that's when things come to the fore, when there's a need for it then people step up and I'm looking forward to seeing that happen on the weekend.
"It's not just about Phippsy coming in and playing well, it's about everyone else fulfilling an extra one or two percent of a role that they may not naturally do when Will's there and the result could be surprising."
Argentina coach Santiago Phelan made two changes to his backline for Saturday's clash with halfback Nicolas Vergallo and fullback Martin Rodriguez dropped, replaced by Martin Landajo and Lucas Gonzalez Amorosino.
Vice-captain Patricio Albacete, a stand-out in the Argentine second-row, will earn his 50th cap, facing Sharpe who will make his 109th appearance.
15 Berrick Barnes, 14 Dom Shipperley, 13 Adam
Ashley-Cooper, 12 Pat McCabe, 11 Digby Ioane, 10 Quade Cooper, 9 Nick
Phipps, 8 Radike Samo, 7 Michael Hooper, 6 Dave Dennis, 5 Nathan Sharpe
(captain), 4 Kane Douglas, 3 Ben Alexander, 2 Tatafu Polota Nau, 1 Benn
Substitutes: 16 Stephen Moore/Saia Fainga'a, 17 James
Slipper, 18 Scott Higginbotham, 19 Liam Gill, 20 Brett Sheehan, 21
Anthony Fainga'a, 22 Kurtley Beale
Lucas Gonzalez Amorosino, 14 Gonzalo Camacho, 13 Marcelo Bosch, 12
Santiago Fernandez, 11 Horacio Agulla, 10 Juan Martin Hernandez, 9
Martin Landajo, 8 Juan Martin Fernandez Lobbe (captain), 7 Juan Manuel
Leguizamon, 6 Julio Farias Cabello, 5 Patricio Albacete, 4 Manuel
Carizza, 3 Juan Figallo, 2 Eusebio Guinazu, 1 Rodrigo Roncero
16 Agustin Creevy, 17 Juan Pablo Orlandi, 18 Leonardo Senatore, 19 Toms
Leonardi, 20 Nicolas Vergallo, 21 Martin Rodriguez, 22 Juan Imhoff