Barcelona have announced that they will report Malaga president Abdullah Al Thani to Spain's anti-violence commission after an insulting tweet was posted from his Twitter account.
The tweet said that the "Catalonian scum" would not get close to winning La Liga and accused the regional press of writing "lies" about Malaga head coach Michel.
The comment was made in response to a Twitter user who jokingly said Malaga should allow Real Madrid to beat them on the final day of the season in a match that could prove decisive in the title race.
Barca feel Al Thani was in breach of fair play with his remark and will refer the incident to the government's Council for Sport, as well as the Royal Spanish Football Federation (RFEF) and LaLiga.
A club statement released on Thursday read: "Barcelona expresses its rejection of and indignation at the contents of a tweet published by the president of Malaga, Abdullah Al Thani, with demonstrations that violate the principles of fair play, ethics and legality that should govern sporting competition.
"For this reason, the club will report this case to the Anti-Violence Commission of the Superior Council for Sport, and will refer the matter to the Competition Committee of the Royal Spanish Football Federation and the Integrity Department of LaLiga."
Michel won six league titles among a host of honours during a 14-year spell in the Madrid senior side, before he later became head coach of the B team.
The 54-year-old insisted this week that he would not grant his old club any favours if the title race goes down to the wire, however.
"It is my Real Madrid, but also my Malaga," he told radio show El Larguero. "I must respect the values I was taught at Madrid, to respect the competition and set out to win every game. My players would not let me look the other way that week.
"I would prefer if it was all over before the final weekend - better to welcome the champions than to knock your old team - but I am a professional."
Barca are level on points with Madrid at the top of LaLiga but sit first by virtue of their superior head-to-head record, although Zinedine Zidane's side have a game in hand.