Fifa is investigating a remarkable bust-up at the World Cup after claims that the Chile striker Mauricio Pinilla was punched by Brazil's communications director Rodrigo Paiva at half-time during Saturday's last-16 tie.
Paiva, a well-known figure in Brazilian football, has admitted to shoving Pinilla, but said that he only did so in self-defence.
A Fifa spokeswoman said: "We can confirm there has been an incident and the disciplinary committee is currently analysing the matter."
The disciplinary panel is believed to have access to video footage and pictures of the incident at the Estadio Mineirao.
A scuffle broke out as the teams headed to the dressing rooms at the end of the first half, sparked by Brazil striker Fred slapping Chile striker Gary Medel on the back of the head as they walked off the pitch.
Brazilian media reports said that Paiva and the Chile assistant boss manager Sebastian Beccacece were involved in a confrontation that ended in the Brazilian official punching Pinilla.
Paiva told Brazilian reporters there was widespread pushing between the two squads, and said: "It was not just me. Pinilla came towards me and I just defended myself. I reacted by pushing him."
Pinilla, who plays for Italian side Cagliari, came off the bench and nearly won the match for Chile, but his shot struck the crossbar in the last seconds of the match, which finished 1-1.
The striker was then one of three Chile players to miss penalties in the shoot-out which Brazil won 3-2 to go through to the quarter-finals, where they will face Colombia in Fortaleza on Friday.
Brazil coach Luiz Felipe Scolari heaped praise on Jorge Sampaoli's Chile and insisted his own team showed tremendous spirit to remain in the competition.
He said: "We knew when the draw was made we were going to be in for a tough time. They're a very organised team with a good tactical system and fine players.
"Every credit to Chile, but this penalty shootout win says a lot about us and about our desire to progress.
"The players can have a break now and, as they recover, we'll have a look at how we won, go through all the tricky situations we were in and a whole lot of other details.
"The idea is to build on this. When you win like this you come out stronger. We're going to tell them that so they can appreciate what they've done."
The victory was savoured by every Brazilian while it also saved English referee Howard Webb from becoming the country's public enemy number one after he found himself at the centre of huge controversy when he disallowed a goal by Brazil forward Hulk for handball.
Sampaoli believes his side were unlucky to bow out of the tournament and can be proud of their efforts.
He said: "I'm not happy. We gave everything we had and we were up against a whole stadium, against the hosts and we didn't go through.
"Our players made history and they did their country proud.
"If that (Pinilla) shot hadn't hit the bar, then everything might have been different, but it wasn't. I hope that the pain that we're feeling right now becomes something else in the future.
"With time we'll look at it differently and we'll come to appreciate what this team has done."