David Luiz insists Chelsea teammate Diego Costa is fully committed to the cause.

Costa has again sparked controversy after his antics during victory over Leicester City.

"I like Diego because he never forgets where he came from," Luiz told Chelsea magazine. "That's why he fights until the end for his team. He never gives up. Diego now plays for one of the best clubs in the world, Diego now plays in some of the best stadiums in the world, Diego is now one of the best strikers in the world.

"But he never forgets when he was playing in the second and third division, with small teams in difficult leagues and difficult stadiums, suffering many injuries and fighting for his career. He never forgets where he came from in Brazil.

"I like these kinds of people, because they really want to give everything. I love the way he plays, and I am happy now because he plays in my team and it's difficult to play against him! It's better to have him on my side. He never makes life easy for the defenders."