"Playing for Chelsea I have to be more ruthless than in the German national team where I've managed to earn myself a different status over the years," Ballack said.
"But it also means that I'm expected to make decisions on the pitch - it's different at Chelsea.
"It goes without saying that everyone is forced to show some restraint so as not to jeopardise our success. But you have to face the challenge.
"You have to make people sit up and take notice of you otherwise you just go under in a team like this, you're just devoured by the machine. And so I've become more ruthless.
"But I wanted to play with all these stars - come hell or high water. Just to be able to prove that I could meet the challenge was well worth the battle for me.
"And now I can say, whatever happens, I've accomplished something. At the same time, I was never worried that I wouldn't succeed."