If you're a champion, you have to have it in your heart.

Now that I'm losing some, I can see how tough I was -- the killer instinct, the single-mindedness, playing like a machine. Boy, that's what made me a champion.

I always looked ahead.

Training the body to obey the mind as I have done differs from the more conventional method of getting the mind to obey the body.

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

Being famous before you've formed your personality, before you have that self-esteem, is dangerous.

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.