Nemanja Matic has refused to rule out the possibility of him one day returning to Chelsea.

The 25-year-old left Stamford Bridge in January 2011 as part of the deal that saw Benfica centre-back David Luiz sign on for the Blues.

Matic has since become a key part of the Portuguese side's starting lineup, but the midfielder has conceded that he would find it difficult to turn down the chance to work under Jose Mourinho.

"To be honest I would like to stay for another year in Lisbon, but surely if someone like Mourinho wanted to bring me back to London, it would be a chance to prove that I can play in the Premier League," he told TMW.

Matic made just three appearances during his stint with the West Londoners.