Cameroon striker Samuel Eto`o is likely to be fined on Wednesday when Spain`s Anti-Violence Commission meets.
The Barcelona forward taunted his former club Real Madrid during his team`s league title celebrations at the weekend.
Eto`o used inflammatory language when he told fans at Barcelona`s Camp Nou stadium that his former club should honour the new champions.
Many of the 98,000 fans at the stadium to celebrate the club`s first league title in six years joined in the chorus.
The commission will punish the 24-year-old if it thinks his words could have incited violence, Spanish national radio said on Tuesday.
The Anti-Violence Commission is expected to make a ruling on the matter on Wednesday.
Eto`o, the league`s leading scorer this season with 24 goals, apologised for his outburst on Monday.
"I have spat in the plate from which I ate," Eto`o said.
"I didn`t want to disrespect Madrid, the club which brought me to Europe and to which I will always be
grateful. It was a mistake."
Real Madrid vice president Emilio Butragueno said his club accepted the apology.
Commission president Rafael Blanco described the Cameroon striker`s words as "unfortunate."
"He has realised his mistake and it is to his credit that he has publicly apologised.
"This is important and will be taken into account."
Meanwhile, Real captain Raul has applauded Eto`o for apologising.
"It is clear that he was wrong, but I am pleased he has put it right and we should stop talking about the incident now," Raul told a news conference on Tuesday.
"I am not one to judge others. Everyone can make mistakes and he has set a good example by asking for forgiveness."
Eto`o arrived at Real as a teenager but, after loan spells with Leganes and Espanyol, failed to gain a regular first-team place.
He then spent five years at Mallorca, although Real retained half his playing rights and traded him to Barcelona.
