Chelsea manager Antonio Conte has talked up the importance of having "warriors" like Diego Costa in his side.
The 28-year-old is the joint-top scorer in the Premier League this season, with his 11 goals helping to fire Chelsea top of the table after 14 matches.
Costa has often been criticised for the aggressive nature of his play during his time in England, but Conte believes that the Spain international is now focusing more on his football.
"I think Diego is a real warrior; he's good for the team, because it's important to have many warriors during the game. Every game is a battle - a sporting battle - and it's important to have warriors in your side. Diego is showing his great passion, and that he can put his passion in the team in the best way. It's fantastic for him and for us, the team, the club and the fans," he told reporters.
"He's playing very well and we're working a lot to involve him in our play. He's improving a lot, Diego. In every game I ask the same things of my players: be focused on the game, be focused to play football. Only this. The other situations don't matter. It's important to be focused on the game. I always ask this of my players before every game.
"It's important to be focused on the game, on the pitch, to do some movements, to put himself in the best way in every moment of the game. To think, to think a lot, to be involved in the game. It's important. If you have to think about the game and try and find the right movement, it's important this."
Chelsea were knocked off top spot by Arsenal this afternoon but will leapfrog their London rivals again if they avoid defeat against West Bromwich Albion on Sunday.