Costa has bagged 13 goals for the Blues this season to fire them to the top of the Premier League.
The Spain striker wanted to join Atletico Madrid in the summer but Antonio Conte didn’t let him go.
Instead, the new Chelsea boss has got him on-side and is now reaping the rewards.
“The one thing Conte has done with Diego Costa is he’s taken the anger towards other players away from him”
Chris Kamara on Chelsea star Diego Costa
Sky Sports pundit Kamara said: “The one thing Conte has done with Diego Costa is he’s taken the anger towards other players away from him.
“He’s channeled that anger into scoring goals.
“All players who played before – or supporters, for that matter – say they’d love to have him in their team as he won’t be messed with.
“Now he’s using that aggression into a different sort of way to win football matches.”
Costa fired Chelsea to the title in 2015 but flopped last season – scoring just 16 goals in 41 games.
Although his anger hasn’t gone completely. Costa has picked up five yellow cards already and is suspended for the Boxing Day clash at home to Bournemouth.