Brazilian sides Atletico PR and relegated Vasco da Gama face record fines and stadium closures after their fans were caught up in violence Sunday.
The shocking scenes of fans kicking and punching each other on the terraces in the southern city of Joinville has provoked a storm -- not least as it harms Brazil's image six months before it hosts the World Cup.
Brazil's Supreme Tribunal for Sporting Justice (STJD), part of the Brazilian Football Confederation (CBF), on Tuesday confirmed it was assessing what punishment should be dished out after violence which Brazilian President Dilma Rousseff said the country would not tolerate.
"Given the seriousness of this case we must make a judgement now as everyone wants a response -- we shall not leave it til 2014," said STJD chairman Flavio Zveiter, adding the Tribunal would likely hold an extraordinary session on the case.
Additional controversy erupted after it emerged police were only on duty outside with private security drafted inside, a decision which had police and state government firing accusations and counter-accusations at each other Tuesday.
The STJD could hand both clubs as much as a 20-game stadium ban and a fine in the region of $50,000 dollars.
Match referee Ricardo Ribeiro faces a four-month suspension if he is found to have officiated a match "without adequate security," Zveiter told Lance sports daily.
Atletico were playing in Joinville, some 150 km (90 miles) south of their Curitiba home -- the latter is scheduled to host World Cup action in June -- after previous disorder.
Sunday's match was suspended for more than an hour after fans fought running battles before security forces belatedly intervened. Four fans were injured.
STJD prosecutor Paulo Schmitt on Tuesday ruled out any possibility of accepting a Vasco request to have the match replayed on the grounds it was stopped for more than an hour.
Brazilian federation rules provide for a match being annulled following a stoppage of more than one hour but Schmitt ruled that out as a ploy.
Atletico chairman Mario Celso Petraglia went further, telling the club's radio station that Vasco fans "sought in premeditated fashion to cause trouble so that the game would be called off - a last-ditch hope of avoiding going down to the second division."
Vasco's defeat sent them down alongside outgoing champions Fluminense, on a doubly black day for Brazilian football.
After Sunday's violence, FIFA insisted a comprehensive security plan will be in place for the World Cup at 12 venues to ensure the safety of all concerned and Andrei Rodrigues, a Brazilian justice ministry official dealing with security during major events, said that what happened in Joinville "will not happen again during the World Cup."
He added that "an integrated security scheme" would be backed by 200 cameras monitoring venues, with "clear intervention plans" to nip potential trouble in the bud.