Diego Costa has revealed Jose Mourinho was the reason he decided to leave Atletico Madrid for Chelsea in 2014, as he prepares to take on the Portuguese’s Manchester United side on Sunday.

The Brazilian-born Spaniard fired Mourinho’s Blues to the Premier League title in his debut season and looks set to do so again for Antonio Conte this time around – despite suffering a tremendous drop in form last term, when Mourinho was sacked.

His sacking was believed to be because he could no longer motivate the players but Costa has admitted he owes a lot to Mourinho for how his career in England has panned out.

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“In all honesty I always tell people I am grateful to Mourinho because he helped me a lot,” Costa told Sky Sports.

“As a player when you want to improve you always look for the best coach and Mourinho is one of the best.

“I wanted to come to Chelsea because of Mourinho. When I considered Chelsea I thought about the fact that Mourinho was here.

“He is a coach that demands a lot from his players, he wants the maximum.”