Napoli defender Kalidou Koulibaly has been transformed playing in Italy.

So says his former Metz coach Dominique Bijotat.

"I wasn't sure he'd be able to achieve this career," confessed Bijotat to France Football.

“He was still hesitant and every little error would affect him for the rest of the game. Now he has grown, above all on a technical level, but his characteristics remain the same.

“Italy and Napoli are really good for him, so this new culture is making him a defender of a high level."