Pablo Matera has been stripped of the Pumas captaincy and suspended over "discriminatory and xenophobic" social media posts between 2011 and 2013, the Argentine Rugby Union (UAR) has confirmed.
Guido Petti and Santiago Socino have also been stood down from international duty ahead of Saturday's Tri Nations meeting with Australia at Bankwest Stadium.
Further sanctions could follow for the trio after a disciplinary process was initiated.
A UAR statement read: "The Argentine Rugby Union rejects the discriminatory and xenophobic comments published by members of the Pumas squad on social networks.
"Meeting urgently, the board of directors resolves in the first place to revoke the captaincy of Pablo Matera and request the staff to propose a new captain to the board of directors.
Comunicado oficial: La Unión Argentina de Rugby repudia enérgicamente los comentarios discriminatorios y xenófobos publicados por integrantes del plantel de Los Pumas en las redes sociales y reunida en carácter de urgencia, la Mesa Directiva resuelve:— Unión Argentina de Rugby (@unionargentina) December 1, 2020
"Secondly, to suspend Pablo Matera, Guido Petti and Santiago Socino from the national team until their disciplinary situation is defined.
"Although the messages were published between 2011 and 2013 and do not represent the personal integrity the three showed during that time with the Pumas, the Argentine Rugby Union condemns any expression of hatred and we consider it unacceptable that those who express them represent our country."
Following the publication of the UAR statement, Matera deactivated his Twitter account.
Matera, Petti and Socino all reportedly published apologies on Instagram before setting their profiles to private.