Having seen a move to Chelsea fall through a year ago, Schurrle is delighted he took the advice of former Blues star Ballack, whom he played with at Leverkusen.
"He told me that, if I had to change, then I had to make this move to Chelsea.
"I always hoped the move to Chelsea would happen. It took a long time. I wanted to come last year, but it didn't work out. It wasn't my decision, it was the decision of Leverkusen. They didn't want to let me go and I had to make the best of the situation.
"It was a missed opportunity, but I said to myself that I had to do my best in every single match and it would come at another time - and so it was. Now, I'm very happy to be here.
"I was confident I would still get this move. When it was clear Jose Mourinho was coming, the first thing I heard was that he wanted me, too. That was really good."