Atletico Madrid have complained to FIFA over an alleged approach from Barcelona to forward Antoine Griezmann.
Griezmann has been linked with several of the biggest clubs in Europe but signed a new deal with Atletico in June, which will keep him with the club until 2022.
However, according to reports, Atletico are claiming Barca have made contact with people close to the 26-year-old France international.
And a FIFA spokesman said: “We can confirm that we have received a complaint from Atletico de Madrid.”
Barca deny the claims and a club spokesman told Spanish paper Marca: “Barcelona have not negotiated with any player, so we understand that no irregularity has been committed.”
Barcelona are currently top of the La Liga table, six points clear of Atletico in second.
And Sky Sports expert Guillem Balague told us earlier in the week that Barca are in position to sign Griezmann in the summer, despite interest from Manchester United.
Despite having signed a new deal with Atletico, Griezmann continues to be linked with some of Europe’s big guns
Balague said: “United are not the only team interested in Griezmann.
“Barcelona are willing to match his €100m buy-out clause and the club’s president, Josep Maria Bartomeu, has met Griezmann’s family for lunch. That’s because he doesn’t have an agent and his sister looks after his affairs.
“But it wasn’t only his sister that was there. Perhaps, tellingly, his parents were in attendance too.
“Griezmann will leave next summer for either United or Barca, but the Catalans are favourites at this moment in time.”
Griezmann enjoyed a superb 2016, helping Atletico to reach the final of the Champions League and winning the Golden Boot with six goals, as France reached the final of Euro 2016.
He finished third in the Ballon d’Or voting that year, behind only Lionel Messi and Cristiano Ronaldo.
Griezmann joined Atletico from Real Sociedad in August 2014 and has averaged more than a goal every other game in La Liga.