I train six days a week for four to five hours a day. I like to keep the same schedule when I'm in camp for every fight.

That's the most terrible mistake you can make: to relax. It's difficult to become a champion, but it's more difficult to maintain it for many years because you're getting too comfortable.

I have decided to make a personal message to David Haye. I want him to fight me, to be a man. I wish there will be enough excitement, pressure and courage for David Haye to fight me.

You have to learn the opponent psychologically inside out and mental strength is one of the important makers. You're either gonna break it or make it.

I learned in my Ph.D. the discipline I needed to be successful. Most boxers are not that disciplined. They have talent, but the self-organization - the ability to schedule yourself and your priorities - is lacking. My studies were about the control of training on both the psychological and the physical side.

My father told and taught me that the word, can hit harder than the fist.

This guy [Tyson Fury] really wants to prove himself in the ring and confirm what he keeps telling everyone, that he's the best in the world.