Real Madrid coach Jose Mourinho has taken legal action against Marca editor-in-chief Roberto Palomar, while the club has asked its lawyers to consider a case against former Barcelona vice-president Alfons Godall.
The lawyers have been called in after both Palomar and Godall made strong personal attacks on Mourinho after Madrid's last two games.
In a story published in Marca on Monday, headlined "It is never the coach's fault", Palomar criticised Mourinho for heaping the blame on Real's players for losing 1-0 at Sevilla the previous night.
According to Palomar, the coach's attitude was: "We have won, they have lost. From the manual. The type of person who flees after knocking someone down."
On Thursday evening, Marca's website quoted Mourinho's legal representatives as saying: "In our opinion, this expression is pejorative and its use was totally uncalled for given the context.
"The Real Madrid manager believes that the comparison made by Roberto Palomar is damaging to his honour and reputation. In addition, Mourinho is demanding €15,000 compensation for the aforementioned breach of his rights, a sum that will be donated to the Canillas football club in Madrid, where his son is currently playing."
Real Madrid's lawyers are considering their legal options over Godall, who was vice-president of the Catalan club from 2003 until 2010 during Joan Laporta's presidency.
Immediately after Tuesday night's Champions League game against Manchester City - when Mourinho slid on his knees onto the Estadio Bernabeu pitch after Cristiano Ronaldo's 90th-minute goal had put his side 3-2 ahead - Godall tweeted: "Lamentable the psychopath celebrating goals as if he were a player. It will be to make up for the frustration at having been useless when he played."
He followed that with: "In the last five minutes, the psychopath's team just about managed to save the three points. A pity! It's true they were up against the wall, but..."
These tweets were widely published in the Spanish media on Wednesday. On Thursday afternoon, Madrid released a statement on their website saying the club had asked its lawyers to consider what action to take against Godall.
It read: "Real Madrid FC would like to firmly reject the defamatory remarks made by the ex vice-president of FC Barcelona, Alfons Godall, about our manager, Jose Mourinho, in the wake of the match on Tuesday between our club and Manchester City.
"Real Madrid FC condemns this attack and has asked its legal teams to undertake any legal action that they deem to be appropriate. Real Madrid FC will not tolerate attacks of this kind and will always bring action against any party which jeopardises the honour of those who are part of our club."
Godall himself was quick to reply, pointing out that Real had supported Mourinho after he poked Tito Vilanova in the eye last year, and saying he would fight any legal case.
"They say Madrid will take legal action against me for discrediting Mou. It would be something if they denounced him for assaulting our coach," he said.
He later tweeted: "If I receive any legal action it will be contested at the opportune moment by my lawyers."
Mourinho's relationship with the Spanish media has been difficult throughout his time in Madrid. In July, his lawyers initiated similar proceedings against El Pais journalist Carlos Boyero for writing that the coach was a "Portuguese Nazi".
Last season, Mourinho withdrew completely from pre- and post-game media duties for a fortnight in protest at what he viewed as biased anti-Real reporting. After Tuesday's game, he accused reporters of being disappointed that Madrid had come from behind to beat City 3-2.