Thiago Motta has been interviewed by police in Paris after authorities launched a preliminary investigation into Bastia striker Brandao head-butting the Paris Saint-Germain midfielder at the weekend.
Motta, 31, and PSG had stated they do not want to press charges in the wake of the incident, which left the Italy international midfielder with a broken nose after Brandao accosted him in the Parc des Princes tunnel following the French champions' 2-0 win on Saturday.
However, police are looking into whether assault charges should be brought against the former Shakhtar Donetsk and Marseille forward.
Europe 1 reports that police have already talked to Motta and will speak to Brandao in the coming days.
The Brazilian, who only joined Bastia from St Etienne on a one-year deal earlier this summer, faces a ban of up to two years from the French Football League (LFP).
The LFP's Disciplinary Commission will meet on Thursday to review the case, and is likely to provisionally suspend the 34-year-old before a full hearing takes place in three weeks' time.