Diego Costa
Diego Costa has scored five goals in his last five appearanaces. Getty Images

Speculation linking Chelsea's Diego Costa with a return to Atletico Madrid has returned in his homeland, just one week before the Spanish transfer window is due to close on 29 January. AS claims Atletico boss Diego Simeone "dreams" of the striker returning to the Vicente Calderon, while the striker also "desires" the move.

Sport believes, however, that Chelsea are reluctant to negotiate a departure during the current mercato, as the striker has hit five goals in his last five appearances under new interim boss Guus Hiddink.

Early this month, AS claimed that Simeone had made a personal phonecall to Costa regarding a move. The striker is understood to have asked Simeone for guarantees that he would remain as Atletico manager next season before he considered leaving Stamford Bridge.

The Spanish publication now claims that Simeone has asked the board to make an official offer before the end of the transfer window.

Atletico are currently leading La Liga, ahead of Barcelona and Real Madrid, and have also qualified for the Champions League last 16 and the Copa del Rey quarter final – having secured a goalless draw in the first leg at Celta Vigo.

Simeone is convinced his side can replicate the success of the 2013-2014 season – when they won La Liga and reached the Champions League final – but believes that he needs Costa to do it, as his striking options of Jackson Martinez, Fernando Torres and Luciano Vietto have struggled in front of goal so far this campaign.

Additionally, with the club unable to make any signings next summer and next January due to a Fifa ban, Simeone is well aware this window will be probably the last chance to get Costa back.

The striker himself hinted at that possibility in December, after former manager Jose Mourinho dropped him to the bench against Tottenham Hotspur and Bournemouth.

"You never know – look where Filipe Luis is now. Life is full of surprises," he said in an interview with Onda Cero. "I always wish Atletico the best and I always follow them, I support them from afar."

Atletico Madrid president Enrique Cerezo also refused to rule out his return. Speaking to RTVE he said: "Right now, Diego is a Chelsea player and he has to focus on Chelsea. But you never know what will happen in football and sometimes players do return to their former clubs."