Chelsea face a battle to keep hold of goalkeeper Thibaut Courtois.
The Sun says the young Belgian has taken the Spanish League by storm during his 18 months on loan at Atletico Madrid.
Now Barca have identified Courtois as a potential Nou Camp replacement for Victor Valdes.
Courtois, 20, has yet to play for the Blues since signing in an £8m move from Genk in July 2011.
And he has made it clear he wants to stay in Spain playing first-team football.