Brandao has issued and then withdrawn an apology to Thiago Motta for head-butting the Paris Saint-Germain midfielder, while the French champions expressed surprise that Bastia will take no action against the Brazilian striker.
Brandao, 34, was captured on the Parc des Princes' closed circuit TV system waiting in the players' tunnel at the end of his team's 2-0 defeat in the French capital on Saturday before approaching Motta, 31, and butting the Italy international.
Motta was left with a broken nose, but PSG declined to press charges against Brandao, who published an apology on his Facebook page on Monday before later deleting the comment.
"First of all, I would like to apologise to my colleague Thiago Motta and to my other colleagues for this error," the Facebook post read. "I am sorry for my attitude, and I count on the understanding of my friends and my fans. And may God bless you."
Earlier in the day, Bastia had published a press release on their official website in which they "condemned without ambiguity" Brandao's actions, though they stopped short of announcing they would punish the player before the French Football League's Disciplinary Commission had looked into the matter.
In response, PSG issued a statement on their own official website expressing "surprise at the absence of a punishment from the club for their player, whose premeditated gesture of a rare violence is inexcusable and deserves an exemplary sanction from the Football League's Disciplinary Commission."
An initial probe should take place when the commission sits on Thursday, with Brandao, who only joined Bastia on a one-year deal this summer, likely to be provisionally suspended before a full hearing in three weeks' time, according to L'Equipe.
Motta's agent, Alessandro Canovi, declared his surprise that Bastia -- whose coach, Claude Makelele, had announced he would sanction his player himself -- were not taking immediate action.
Also, in response to Bastia's claim that there had been "certain players who did not stop insulting and provoking their opponents," Canovi denied his client had been the instigator.
"I consider it nonsense and above all great hypocrisy to paint Thiago as a provocateur, as if they were trying to justify the cowardly ambush of which he was a victim," he told Goal.com. "I am also saddened by the fact that there is another victim in this: the public, especially the youngest ones, who saw this incident via TV or social networks. A premeditated and violent act that I still consider a real ambush."