Veteran centre Lisandro Arbizu was confirmed as captain when Argentina finalised their squad for the World Cup.
Lisandro Arbizu will captain Argentina down under
The centre joined front-row forward Federico Mendez and lock Pedro Sporleder as coach Marcelo Loffreda cut his provisional squad of 38 to 30.
Also making the squad were another lock, Patricio Albacete, and back rowers Martin Durand and Pablo Bouza.
Arbizu will captain the Pumas for the second consecutive World Cup, having led them to their best finish in 1999 when they upset Ireland to reach the quarter-finals.
Scrum-half Agustin Pichot has recovered from an ankle injury and will play.
"We feel like we can play with anybody right now," Loffreda said.
"Our goal is to repeat or better our performance in (the 1999 tournament)."
At the cup in 1999, Argentina reached the quarter-finals, a first for the South American team.
The Pumas meet Ireland again in Pool A of this year's tournament after facing hosts Australia in the tournament's opening match in Sydney on 10 October.
Romania and Namibia are also in the group.
Backs: Diego Albanese, Lisandro Arbizu (captain), Felipe
Contepomi, Manuel Contepomi, Ignacio Corleto, Juan de la Cruz
Fernandez Miranda, Nicolas Fernandez Miranda, Juan Martin
Hernandez, Jose Maria Nunez Piossek, Jose Orengo, Agustin
Pichot, Gonzalo Quesada, Hernan Senillosa
Forwards: Patricio Albacete, Rimas Alvarez, Pablo Bouza,
Martin Durand, Ignacio Fernandez Lobbe, Roberto Grau, Omar
Hasan, Mario Ledesma, Gonzalo Longo, Rolando Martin, Federico
Mendez, Lucas Ostiglia, Santiago Phelan, Mauricio Reggiardo,
Rodrigo Roncero, Martin Scelzo, Pedro Sporleder.