He guided Chelsea to Europa League glory and third in the Premier League in his first season at Stamford Bridge.
But Sarri is tipped to be on his way to Juventus and Fabregas has lifted the lid on playing under him.
ASM's January signing said, "He is very superstitious, he is very stubborn in this way.
"He is a manager with his own ideas and he doesn't move from them much.
"He has an idea of how he wants to play and the football that he really wants to play. He doesn't move from it. No matter what you tell him, no matter what you advise him, no matter what your opinion is, he will never change.
"But he did it the way he likes it. He has his own vision of football and, in the end, he is where he is with it and you have to respect that."