Mata has shone for the Blues in recent weeks and was rewarded for his performances with the September player of the month award.
The Spanish international has revealed that things have not changed dramatically at Stamford Bridge since Di Matteo replaced Andre Villas-Boas as Blues boss.
He told Absolute Radio: "We're playing with freedom, Eden Hazard, Oscar and me. We all three love to play with the ball, and our relationship with each other is very good.
"I mean it's not changing a lot of things from Andre, they were working together, so they know each other very well. I think when you're a manager you play or the way that you play, is because of the players that you have.
"Di Matteo he is a very, very good manager, he's so clever, he knows very well how is playing and managing for Chelsea. He used to be a legend here. So it's very important for us to have a manager like him."