Rio de Janeiro, Brazil - Brazil's authorities were put on notice last week after the World Cup's first football riots broke out in Belo Horizonte, where hundreds of Argentinian hooligans clashed with security forces.
The Argentinians caused substantial damage in the streets of the central host city, but that was not the focus of the media coverage of the riots. What caught Brazil's attention was a new song that the Argentinians were chanting, which has since caused a stir in Brazilian media.
Brasil, decime qué se siente, tener en casa tu papa - Brazil, tell me how it feels, to be bossed around in your own home. The song continues with references to past football victories against Brazil and a warning that Brazil will see [Lionel] Messi later in the World Cup. It ends with another bold statement: Maradona is greater than Pelé.
The insulting chant, which has been dubbed the unofficial Argentinian anthem for this World Cup, is the latest addition to the repertoire of the decades-old football rivalry between the two South American giants.
Brazilians on social media have responded in style, invoking their country's superior football history, which has traditionally dominated Argentina. Brazil won the World Cup five times and is the only nation to have played in all editions of the tournament. Argentina won it twice.
Battle of the South Americans
The intense rivalry has for years been called the "Battle of the South Americans", because of the sheer level of competitiveness between the two nations. The never-ending discussion about who is the better player - Maradona or Pelé - has neatly evolved with time as Messi and Neymar were declared as their respective successors.
Speaking to Al Jazeera in Rio de Janeiro, Fabio Piperno, one of Brazil's foremost football commentators, said much of the animosity stems from the historical struggle over continental hegemony in South America.
"In the 1920s and 30s Argentina had already reached a certain level of development which made it one of the largest economies in the world. In contrast, Brazil was very underdeveloped at the time. And so the Brazilians looked to the Argentinians with jealously, thinking; they are right next to us, they are so rich, so sophisticated. Why can't Brazil reach this level of prosperity?"
In that age, Argentina's perspective was very different from that of Brazil's. In the 1930s, the Argentinian economy was five times larger than the Brazilian economy and with its major European influences, it looked for inspiration far beyond its northern neighbour. Brazilians have therefore referred to Argentinians historically as snobbish WASPs.
"If we look at the 20s and 30s, Argentina was much more important than Brazil when it comes to football," Piperno said. "When there was an Argentina-Brazil match, it was a chance for Brazil to impose itself on its large neighbour. But with the arrival of Pelé, everything changed."
Whispers of a final
More than 100,000 Argentinians have crossed Brazil's southern border in support of their national team; a mass migration described by Brazilian media as nothing short of an invasion. Most of them are expected to be in Sao Paulo on Tuesday, when Messi and co will take on Switzerland in the round of 16.
The distant possibility of a confrontation between Argentina and Brazil already has hearts racing, especially because both teams can only meet each other in the final game of the tournament. For many in both countries this would be the ultimate climax of the Brazil 2014 World Cup.
"To lose to Argentina in Brazil would be an eternal pain - a blow that Brazil would truly never overcome," Piperno said. "It would be the biggest blow, not only in football, but in the history of Brazilian sport. It's hard to imagine, but it would leave a huge emotional trauma."