AC Milan defender Simon Kjaer is convinced by the potential of Chelsea centre-half Andreas Christensen.
The pair are currently together with the Denmark squad.
Kjaer said of his defensive partner: “I think he has all the conditions to become the best defender in the world. He reads the game in a unique way. In addition, he is fantastic on the ball, fast and athletic.
“Every now and then he has to shout a little louder, although he has made strides. I think AC is a great defender. He has developed both on and off the field during the time that he is here (with the Danish team).
"But I want to see more of Andreas: I want more personality. He's made some progress, but I want to keep pushing him a little bit on that front. I want to demand more from him, both on and off the field. He has become better and as far as I'm concerned he can decide for himself how big he wants to be."