Zverev: "I can do a lot of damage when I play like this".

Alexander Zverev has qualified for the quarter-finals of the Australian Open, following his four-set victory over Ugo Humbert.

He spoke about his chances in this tournament and how he feels about his current game.

He declares: "All players who reach this stage play very well. Anyone who reaches the quarter-finals or semi-finals deserves to do so.

There's no easy way to get there. Sometimes the draw is a little more open, and other times you beat players who feel uncomfortable against you.

To reach the quarter-finals, you have to play great tennis. In my head, I know I'm playing well. I can feel it on the court.

I feel I can do a lot of damage when I play like that, but my opponents feel the same.

From now on, it's only going to be tough battles."

He will face Tommy Paul in the quarter-finals in Melbourne.