Barcelona will reportedly face a legal investigation from the Spanish Football Federation in response to the acquisition of Antoine Griezmann from Atletico Madrid.
The La Liga champions finally secured the signature of Griezmann for a fee of £108m earlier this week after initially establishing their interest in the Frenchman last summer.
The club claim that the deal went through after activating a clause on Griezmann's contract which allowed him to leave for £108m on July 1.
However, according to The Mirror, Atletico believe that since Barcelona started negotiations for the forward in March, they are owed another £71.8m due to a previous clause in his contract.
Atletico are yet to lodge an official complaint, but the federation - who prosecuted Barcelona following their acquisition of Neymar in 2013 - are nonetheless set to open a file on the move.
Diego Simeone's side have splashed out £116.8m on striker Joao Felix as a replacement for Griezmann, who had spent five seasons in the Spanish capital.
Germany
Hungary
Scotland
Switzerland
Albania
Croatia
Italy
Spain
Denmark
England
Serbia
Slovenia
Austria
France
Netherlands
Poland
Belgium
Romania
Slovakia
Ukraine
Czech Republic
Georgia
Portugal
Turkey