Single-mindedness. I hate to say it because I don't think it's the best thing for developing a person, but the single-mindedness - just concentrating in the one area - that's what it takes to be a champion.

In tennis, at the end of the day you're a winner or a loser. You know exactly where you stand... I don't need that anymore. I don't need my happiness, my well-being, to be based on winning and losing.

If you're a champion, you have to have it in your heart. You can have the greatest coaches in the world, all the opportunities to play, and the greatest equipment, but if you don't have it inside, you're not going to make it. On the other hand, if you don't have any of those luxuries but you have heart and courage and the guts to go out there and grind it out, then you'll make it.

Every time, all the time, I'm a perfectionist. I feel I should never lose.

Whatever your goal in life, be proud of every day that you are able to work in that direction.

Find something that you're really interested in doing in your life. Pursue it, set goals, and commit yourself to excellence. Do the best you can.

If you can react the same way to winning and losing, that's a big accomplishment. That quality is important because it stays with you the rest of your life, and there's going to be a life after tennis that's a lot longer than your tennis life.