The decision means the trio will miss Saturday’s Test match against Australia.
“The Argentine Rugby Union strongly repudiates the discriminatory and xenophobic comments published by members of the Pumas squad on social media,” said a statement from the governing body.
It added: “Although the messages were expressed between 2011 and 2013 and do not represent the integrity as people that they have shown during this time with Los Pumas, from the Argentine Rugby Union we condemn any expression of hatred and we consider it unacceptable that those who express them represent our country.”
The derogatory posts include remarks directed at Bolivian and Paraguayan domestic staff, women, Black people and insults about religion.
In a video posted by the Pumas on Twitter, Matera apologized that the team’s tribute — which, according to Argentine newspaper Clarín, amounted to wearing black ribbon on their shirt sleeves — “caused disappointment.”
The board of directors decided to revoke flanker Matera’s captaincy and suspend him alongside second-row Petti and hooker Socino following an emergency meeting, according to the ARU, which also said that it has resolved to start a disciplinary process.
The three players will remain suspended until that process has concluded and the board also requested that staff present a new captain to them to replace Matera.
The players have now closed their Instagram accounts to the public and their profiles are no longer available on Twitter, but before doing so they released apologies that were published by Argentine media. CNN was unable to verify the posts given the closure of their accounts, but screen grabs of the derogatory comments have been widely shared by Argentine media and on social media.
According to Clarín, Matera released a post on Instagram on Monday in which he claimed to feel “very ashamed” and apologized to “all those who were offended by the atrocities I wrote.”
He added: “Today I have to take responsibility for what I said nine years ago. I’m also sorry to my team and my family for the moment they are going through because of my actions and thanks to the people who love me for their support.”
In screen grabs visible in a report by Clarín, Socino asked for “forgiveness from those who may have been offended by what I said,” while Petti said his posts “do not at all represent the person I am today. I made a mistake and I wanted to express my sincerest apologies.”
CNN has contacted the players via the ARU and their representatives but did not immediately receive a response.
Having started its Tri Nations campaign with an historic victory over the All Blacks and a draw against Australia, Argentina was defeated 38-0 by New Zealand over the weekend.
Given the points difference between the teams, it is highly unlikely that Argentina or Australia will be able to overtake New Zealand at the top of the Tri Nations table in their final game.