The Atletico Madrid forward is tied down at the Metropolitano until 2030 with a monster €500 million release clause, but that hasn't stopped Barcelona coming knocking, according to the complaint. Atletico's lawyers spent the past week building their case, gathering messages, calls and paperwork before finally pulling the trigger on Tuesday evening.
"Our responsibility is to defend Atletico de Madrid's interests, and that is why we are going to file a complaint with FIFA against Barcelona for negotiating with a player under a valid contract during the protected period," stated Miguel Angel Gil, Atletico Madrid's chief executive.
Gil made that threat a week ago in comments to EFE, and he has been true to his word. Atletico's case rests on the claim that Barcelona held direct talks with Alvarez despite his long-term deal sitting well outside the six-month window in which approaches are legally allowed under FIFA's rules.
The timing could hardly be more explosive, landing in the middle of the World Cup with Alvarez out in the United States with Argentina. The 26-year-old poured fuel on the fire himself after Argentina's group-stage win over Austria, when he made no secret of wanting out of Atletico Madrid.
"I think the best thing for everyone is a transfer, and I want to fulfil my dream," Alvarez said to ESPN
Those comments haven't shifted Atletico Madrid an inch. The boardroom is refusing point-blank to negotiate with Barcelona, and there is zero sign the €500 million clause is coming down, whatever the player or his suitors want.
Atletico's hierarchy believe Barcelona's approach has unsettled a player central to Diego Simeone's plans for next season, and the formal complaint is designed to force FIFA's hand and open an investigation into how those talks were conducted. A rivalry already soured by years of transfer-market needle has now boiled over into all-out institutional conflict.
Barcelona have stayed silent on the complaint. Alvarez, for his part, remains with the Argentina squad, keeping his focus on the World Cup while the row over his future rages on back home.