Maurizio Sarri said David Luiz can play his way of football, while the Chelsea head coach has been surprised by the defender as a "player and a man" since replacing Antonio Conte.
Brazilian centre-back David Luiz was frozen out by former boss Conte last Premier League season but the veteran is back in the fold under Sarri in 2018-19.
David Luiz has been a mainstay this term, playing in all seven of Chelsea's Premier League fixtures, including the 1-1 draw at home to Liverpool.
And former Napoli boss Sarri lauded the 31-year-old's ability after he appeared set to leave Stamford Bridge.
"He is much better than I thought before [I arrived]," said Sarri. "Much better, as a player and a man.
"I don't know what happened before but when I arrived immediately I had a feeling he is a very good player for my way of football as he is a very technical centre-back.
"I appreciate very much the man as he is direct. If he has to say something to me, he does that."
Sarri added: "I like direct people. Very much.
"He was a little confused as two seasons ago he was a protagonist but then came six months without playing. So he was a little confused.
"I think he is very able to play my way with his characteristics. He is very technical and understands the action of the defensive line very much."