Everton boss Sean Dyche admits he fought to keep Jarrad Branthwaite over the summer.
The centre-half has been outstanding for the Blues after returning from loan last season with PSV Eindhoven.
Dyche said: "I was making it clear he wouldn't be a player who was available. I knew there were certain players who had to leave the building, whether I wanted them to leave or not, we had to bring down the wage bill a little bit. So I made it clear - 'no he's one I want to be in the building and I see development in him'.
“I think you can never define someone's character, but even last season speaking to him on the phone a couple of times when I first got here, I could tell he was very level, he was enjoying the experience [at PSV], he was taking on the challenge.
“He was very unlucky in pre-season, missed a couple of weeks, but he seemed to be quite an assured character, quite a calm character. I like that in all players, but particularly in centre halves you want that. His adaptation has been quite clear to the pace and the detail of Premier League football, I think he continues to improve, and physically he is a good specimen, we know that.
"But I must say he is playing in front of a very good goalkeeper and a very good centre half next to him in James Tarkowski, which I think helps as well, Myko [Vitalii Mykolenko] is improving all the time and Youngy [Ashley Young] was playing next to him early season too, an older head speaking to him all the time, so these are the things which improve you as a player. But a lot of credit to him for taking it on himself by the way."