He came to fruition under the guidance of Arsene Wenger at Arsenal, before playing for Pep Guardiola at Barcelona.
"I think with Mourinho, he played with my mind in a different way that nobody else played before," he told The Coaches' Voice of his time at Chelsea.
"He gave me also another type of trust because unconsciously I know Arsene, for example, that I really had a lot of trust with as well. I was like his son, he took me when I was 16 and he made me improve slowly, slowly, until I was a man.
"With Mou, it was a little bit more in terms of the feeling personally and how we speak every day.
He would send me messages, he would speak to me nearly every day and he would speak to me in a manner where he makes me see that I'm one of the most important players in the squad and that always had a really powerful message in my brain and that's why I played such good football under him."