Atletico Madrid boss Diego Simeone has not ruled out the prospect of Chelsea forward Diego Costa returning to the Vicente Calderon during the January transfer window, according to AS.


Costa had the most prolific season of his under career under Simeone in 2013/14, when the Spain striker’s haul of 27 league goals fired Atleti to an unlikely La Liga title triumph.


He joined Chelsea shortly afterwards, but his Stamford Bridge future appears unclear after a mixed 18 months at the west London club.


According to AS, Simeone has made it known to the 27-year-old that he wants him to rejoin the Spanish capital club.


And sources close to the forward have suggested that Costa wants to go back, although he wants assurances from Simeone that he will still be on the Atleti bench next season before seeking a way out of Chelsea.


It would be a very difficult operation for Atletico to pull off, as it would probably require the departure of summer signing Jackson Martinez.