Marseille midfielder Joey Barton has been ordered to appear at a disciplinary hearing on April 15 after insults on Twitter directed at Paris Saint-Germain captain Thiago Silva caused a storm.
Paris Foot Gay, an amateur club with a large number of gay players who campaign against homophobia in football and society as a whole, complained to France's Professional Football League (LFP) after Barton called Brazil defender Silva a "pussy" and "a overweight ladyboy" on Twitter on Wednesday.
The matter has since been passed on to the Conseil National de l'Ethique (CNE), who have the power to hand the Englishman a suspension for remarks that have been taken very seriously in France.
PSG issued a statement on Wednesday evening describing Barton's words as "unacceptable".
"These attacks are serious and go beyond mere verbal jousting," PSG added, saying both the club and Silva would consider what action to take in response.
Marseille, with whom Barton is on loan for the season from Queen's Park Rangers, responded by saying they had called on their player to desist and "put an end to the controversy."
Sports daily L'Equipe led with the story on Thursday morning, their front page carrying a picture of Barton next to the headline: "Is that what you call British humour?"
Inside, the paper lambasted the Englishman, describing him as "an average player," and casting doubt on his future in Ligue 1.
The controversial Barton's loan deal expires in the summer and no talks have yet taken place to extend his stay.