Yannick Carrasco has entered negotiations with Atletico Madrid over a new contract, according to AS.
Chelsea are believed to have identified the Belgium forward as a target for the January transfer window but Atleti do not want to let him go.
Atleti are in talks with the 23-year-old over a new deal. They want to extend his current deal, which expires in 2020, by a further two years, while they also want to increase the value of his €40m (£36.2m) buyout clause.
Chelsea are aware that the player is happy in Spain and know that he is in discussions over a new contract at the Vicente Calderon.