Mourinho believes the Belgian will be a regular starter at Everton.
"It was something he was very keen to do. The kid wants to play every weekend. I don't know if Roberto [Martinez] promised him that, but the kid is more keen on that than competing every week against other big players for a position.
"He's a great kid and that's why we don't want to sell him. We didn't sell him when we had good proposals to do it. We all believe he is a player for many years at Chelsea. When the player is happy to go and we got Samuel, it was a good way to resolve the situation because we kept three experienced players for a position that demands a lot, and at the same time we let him go, and go happy."
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