Petr Cech's future at Chelsea is in doubt. Thibaut Courtois says the club have fears over the fitness of Cech.

Courtois, on loan at Atletico Madrid, told Spanish radio station Onda Cero: "I know he has problems in his knees and on his back.

"Chelsea's goalkeeping coach told me he doesn't know how much time Cech can play at the top level."

Chelsea paid Genk £8million for Belgian stopper Courtois this summer, then loaned him to Atletico as a replacement for Manchester United's David De Gea.

Courtois added: "Chelsea told me to spend two years at a club like Atletico. After that one season in an English team so I can integrate myself into the Premier League."