When I know that I have played as well as I can. It doesn't matter so much whether I have won or lost. But being completely satisfied with myself? That's something that never really happens to me.

The coaches of some players who are my own age keep saying publically about me: This guy is going to be one of the greats. I am clever enough to know that they do not truthfully think so. They are trying to shake my confidence. Of course, this is a matter of tactics.

I know that I have the potential. And the opportunities. But I don't say: I want to win the Australian Open in 2018. It doesn't work that way.

I am surprised by what people expect of me.

I try to pay as little attention as possible to people who are not part of my team. What counts for me is what my father says, because he is my coach. I listen to my brother and my fitness coach. I don't care about anyone else.