Manchester United boss Erik ten Hag has revealed how Casemiro is mentoring Kobbie Mainoo.
Ten Hag says the Brazilian has been good for the young midfielder.
"Kobbie is very coachable, Casemiro has so much experience and Kobbie will learn a lot from him and that can accelerate his development," he said.
When they play together I think they can take benefit from each other.
Casemiro takes that responsibility, he takes it to him, he is talking to him, I see it in the dressing room, I see it on the pitch in games, I see it in training.
Of course he looking at his own game but he's trying to help and support Kobbie. Absolutely there is that bond (between them)."
On Mainoo, Ten Hag said: It is more easy to integrate young talent into a successful team. That's true.
The conditions where we had to bring in Kobbie Mainoo were not so good that we knew beforehand that it would be a success. I had the confidence because I saw him performing and progressing in spring and summer.
When I brought him in for the game against Arsenal, I didn't have any doubts. But when he comes into the team there are many things he has to do on his own because when there are a lot of routines in the team it is much easier for him to come in.
But we were not in that situation - and I don't think this club has been in that situation for a long time.
For many years, United have not been in that (successful) position, so we are building a team that can offer a foundation for young players to come in.
We have to have a foundation so that we can add quality players to the squad to take the team to the next level."