I've been motivated by overcoming challenge and overcoming the hurdles and obstacles that face me. There still is plenty out there to get motivated by.

It's shocking how little there is to do with tennis when you're just thinking about nothing except winning every point.

If you don't practice you don't deserve to win.

I had moments of my actions and words not reflecting who it is I am - if that defines a punk, then yes, absolutely.

Every now and then I will play; I try to focus on charitable work. I might do it because it's an offer I can't refuse, so I rally and try to stay in shape and keep myself active.

It's easier to live with disappointment than regret.

First of all, in any sport where you can measure distance, height speed and all of that, you see how athletes have changed their sport and made it better. I believe, with every generation, the sport has improved. Certainly, in the men's game, that has been the case. I think that I played Pete [Sampras] at his best, I played Roger [Federer] at his best.. I believe wholeheartedly that Roger and [Rafael] Nadal have pushed the game much further than myself or Pete ever did. Their options on the tennis court are considerably more than ours.