Chelsea Transfer News: Diego Costa Rumours Addressed by Atletico Madrid Chief

Diego Costa's tough season is getting worse. He's struggling mightily in the Premier League with Chelsea. Now, old club Atletico Madrid don't even want the Spain striker back.

Atleti president Enrique Cerezo has indicated his club won't be active in the January transfer market, according to Charlie Phillippe of the Daily Express: "It's complicated for Atletico to make signings this winter."

Cerezo gave a witty rebuttal to the idea he's still open to bringing Costa back to the Spanish capital: "Then close the door, because it's cold."

Costa's loss of form has been at the root of Chelsea's disastrous title defence this season. He's scored just three times in England's top flight, per ESPN FC.

It's a far cry from the 20 league goals he bagged during the 2014/15 campaign, according to WhoScored.com.

Tim Ireland/Associated Press

Costa provided the fear factor that masked some of the deficiencies in manager Jose Mourinho's team. Specifically, the Blues' sluggish and vulnerable defence.

With Costa around, capable of striking on the break at any moment, opponents were reluctant to commit numbers to attacking Chelsea's back four. Yet, without Costa's subtle and sudden movement that terrorized teams last season, the Blues have been breached a whopping 24 times already, per the league's official site.

His loss of form has led to several spats with manager Jose Mourinho. The Portuguese gaffer squabbled with Costa after chiding the striker for poor movement during Chelsea's win over Maccabi Tel Aviv in the UEFA Champions League, per Dominic Fifield of the Guardian:

Costa threw a notable tantrum when Mourinho left him on the bench for a goalless draw at Tottenham Hotspur in the Premier League, according to Mirror writer Alex Richards.

Atletico know what Costa can do when he's at his best. His 36 goals during the 2013/14 season helped the club win La Liga and reach the Champions League final.

Costa matured from a left-sided forward who offered excellent support to Radamel Falcao the season before into the most feared central striker in Europe.

Paul White/Associated Press

He clearly hasn't lost his love for his old club. Costa recently told Spanish radio station Onda Cero (h/t Sky Sports' Lyall Thomas): "You never know. Look at how well Filipe Luis is doing. Life is full of surprises. I always wish Atletico the best and always follow them and support them from afar."

In fact, Chelsea have been dealing with suggestions Costa will return to the Spanish capital since the summer. Back in June, Fifield wrote in the Guardian how the Blues were ready to rebuff any advances from Atleti.

Since then, though, Costa's regression has been alarming. So much so the club are reportedly actively considering alternatives. The Telegraph's John Percy claims West Bromwich Albion's Saido Berahino is a £20 million target.

Cerezo's words are unlikely to be as welcome as they would have been in the summer given how Costa's Chelsea career has since hit the skids. Instead, Mourinho is left to focus on finding ways to get his misfiring malcontent back on form.