Atletico Madrid president Enrique Cerezo said the club have "evidence" to back them in their dispute with Barcelona regarding Antoine Griezmann's transfer fee.
Barca announced the Frenchman's capture on Friday after activating his €120 million buyout clause, but according to Atletico, the club and player had agreed a deal before his clause was reduced from €200 million on July 1.
Cerezo told RAC1 (h/t Goal's Dejan Kalinic): "If the club have made this statement, it's because there's evidence. We have to study it, and we'll demand the amount we consider to be necessary."
Griezmann signed for Barcelona little more than a year after publicly deciding to stay with Atletico rather than join them:
Shortly after the announcement of his move, Atletico released a statement that read:
"Atletico Madrid considers that the deposited amount is insufficient to cover his buyout clause, since it is obvious that the agreement between the player and FC Barcelona was closed before the clause was reduced from €200 million to €120 million."
Griezmann announced his intention to leave Los Rojiblancos on May 14, which the Spanish club also cited:
"Atletico Madrid believes that the termination of the contract happened before the end of the last season due to facts, acts and demonstrations made by the player, and therefore has already initiated the procedures it has deemed appropriate to protect their rights and lawful interests."
The 28-year-old contributed 133 goals and 50 assists in 257 appearances with Atletico.
Sports writer Andy West thinks he'll be an excellent addition at Barca, but he'll also face challenges ingratiating himself at the Camp Nou:
Griezmann will be able to share their goalscoring and creative burden and provide another match-winning option for the team.
A legal dispute between the club and his former employers is far from an ideal start to his Barcelona career, but on the pitch, he should be an excellent asset as the team look to battle on multiple fronts next season.