Diego Costa's hot-headed displays threatened his future at Chelsea last season but Antonio Conte is reaping the benefits of a player reborn.
Chelsea head coach Antonio Conte believes Diego Costa has reined in his famously fiery temperament to the benefit of his Premier League high fliers.
Conte's side travel to Middlesbrough on Sunday aiming to chalk up a sixth consecutive top-flight victory and Costa's resurgence has been key to their superb form.
The Spain international cut a frustrated figure for much of Chelsea's shambolic title defence last time around, as his on-field spats with opponents and officials often took more limelight than his efforts in the penalty area.