Chelsea defender David Luiz has revealed manager Maurizio Sarri has challenged the players about his methods.
And Luiz says he and his team-mates still believe in Sarri's philosophy.
He said: "We have had many meetings already asking if someone doesn't believe.
"They can say. Nobody said anything. It's because everyone believes [in it]."
Luiz added: "There is a big difference when you have already understood everything, it is much easier to play football. I think we are in the right way to still improve to become a fantastic team."