Chelsea have taken 12 points from a possible 12 this season, proving Maurizio Sarri's style is working well in the Premier League.
The German international has started all four matches alongside David Luiz, and spoke of the new system.
"I played for Roma in Italy so I knew the way the manager liked to play and it was something I favoured. He wants us to press high compared to last season when everyone knows we sat back.
"Now it is different. We create a lot of chances and for me that's very good. Mostly he likes the defenders to play the ball short and keep possession. I have shown so far I can do it but I want to improve every day. He is a coach who is not happy, he is always saying you can do better, and that keeps you alive.
"To be honest, I'm surprised how well we've done because players like Eden Hazard and N'Golo Kante had big World Cups and came back late for training. They are in good shape and that's impressive.
Chelsea continue their season at Stamford Bridge against Cardiff City on Saturday.