The Spaniard arrived in the Premier League in summer 2014 from Atletico Madrid and was instrumental as the Blues won the title last season.

But he was never far away from controversy with his on-field antics and this season he was suspended by the Football Association for three games after clashing with Arsenal's Laurent Koscielny.

To compound matters, Chelsea have made a poor start to the season and Costa defended under-fire manager Jose Mourinho.

But reports in Spain suggest the 27-year-old's future could lie away from Stamford Bridge.