The Chelsea striker has been in red-hot form this term and has already matched his tally of 12 goals from last term.
He’s reached that total from just 15 games and could go on to win the Premier League golden boot this term.
“He can still improve”
Conte’s side are on a nine game winning streak thanks, in no small part, to Costa’s efforts.
But while his boss admits he has been top class, he thinks there’s more to come from the Brazil-born Spain international.
Conte said: “Diego is playing in a fantastic way, I am pleased for him and the fans because he is showing great patience in the right way.
“Now he is very focused on the game, to play football, to make the right movements and to attack the space.
“But he can improve.”
Chelsea travel north to face Sunderland tomorrow looking to keep their place at the top of the Premier League with a 10th win on the bounce.