The attack came just days after celebrating Gay Pride.
A statement from LGBT (lesbian, gay, bisexual and transgender) Rights in Argentina read: "From the Argentina LGBT Federation we are already accompanying them during this terrible moment and doing everything in our power to ensure that the justice system responds quickly and finds those responsible," reported The Sun.
Vivero tweeted Castellari was called a 'f****** s***' and said it's a classic example of discrimination at work just for loving someone of the same sex.
"He doesn't know how many stitches he will need and they need to operate after a fracture in some part of his eye. Everything hurts," he said.
Earlier this year New Zealand's only gay inclusive rugby team, the New Zealand Falcons, revealed an opposition player refused to shake hands with a player post-match after finding out about their sexual orientation.
Read more: Kiwi documentary explores challenges faced by gay rugby players
The prejustice act inspired Auckland University screen production student Nevin Govindasamy to produce a documentary focused on the team, exploring the barriers faced by gay rugby players over their 2017 season.
Godvindasamy was interested as to why a stigma existed in a high-performance sport environment and said the documentary aimed to inspire thought and tangible change in how New Zealand views it's gay players.
As a sport-crazy gay man, Govindasamy said he loved watching rugby but fears of negative and homophobic comments meant he had to avoid even holding hands with his partner on the side line.
"Having to hide any part of my personality I think is so compromising. I would love to be myself wherever I am," he told the Herald.
The first openly gay male to represent his country in sport, Simon Dunn, also recently opened up about his abuse as a gay sportsman.
The Australian was heading home after being out with friends from the Sydney Convicts Rugby Club when he was savagely beaten, he told Attitude magazine.
He woke up the next morning in hospital with a chipped tooth, black eyes and a swollen face. The nursing staff informed him they had intended to put him in an induced coma due to fears of a blood clot in his brain.
"When I tell people about what happened to me they're generally shocked because I am a former rugby player and national team bobsledder with a 6ft1 and 98kgs frame. How could I possibly be a victim of gay bashing. Well, I was. And it proves that no matter how big or small you are, we are all open to the most terrible abuse. And we should never stand for it," said Dunn.
In September, New Zealand Rugby became the first Kiwi sporting body to be awarded the Rainbow Tick, after major corporates such as ASB, Massey University, Spark and NZME, which acknowledged it valued sexual and gender diversity, and had policies in place to reflect that.
Although none of the 1160 players to pull on an All Black jersey has yet come out publically as gay, NZR chief executive Steve Tew believes some may have kept their sexual and gender identities secret.
Tew said the tick signalled the organisation's intentions to be more inclusive - and that extended to the All Blacks environment.
"We can't hide from the fact that, unless there's something completely wrong with the law of averages in the male population, we would have had All Blacks who haven't openly expressed their sexuality as different than we know.
"We clearly haven't created an environment at the community or professional levels where people are completely comfortable to express their sexuality and we need to fix that," Tew said
