Earlier this summer the 28-year-old was reportedly informed by manager Antonio Conte, in the wake of the club’s Premier League title success, that he would not be part of his plans going forward.
Costa has since been searching for a new club and on Thursday, his lawyer Ricardo Cardoso revealed that the Spain international would make a formal transfer request in order to speed up the process.
Cardoso also threatened the Blues with legal action for their “behaviour”, but a spokesman was quick to hit back at a press conference today ahead of this weekend’s Community Shield game.
“If I may I would like to say something on behalf of the club. We don’t usually respond to comments of this nature, but I think we should do on this occasion,” he said.
“The premise the lawyer has put forward is just wrong. The decision on Diego was made back in January. The player knew the decision, his agent knew the decision, clearly the lawyer has not been well informed.
“The lawyer’s argument that Antonio as a coach has forced the player out by text message in June is just nonsense. We’ll just have to see what the window brings.”
Asked for his take on the situation, Conte added: “For me it is very simple. The situation is the same as what I said in the past: the player, his agent and the club knew very well the future of the player.
“For sure I don’t understand why the lawyer is getting involved because the situation is very clear.”
A return to Atletico Madrid is believed to be Costa’s preferred option for a move, although the La Liga side are banned from signing new players until January 2018.