After being at the top, I don't think I could play senior tournaments, because you know how good you were. I don't know if I would enjoy that, being half of what I was.

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.

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.

When I play, I'm boiling inside. I just try not to show it because it's a lack of composure, and if you give in to your emotions after one loss, you're liable to have three or four in a row.

When I was in grade school and we had to write papers about what we wanted to be when we grew up, I wanted to be a social worker or a missionary or a teacher... Then I got involved with tennis, and everything was just me, me, me. I was totally selfish and thought about myself and nobody else, because if you let up for one minute, someone was going to come along and beat you. I really wouldn't let anyone or any slice of happiness enter... I didn't like the characteristics that it took to become a champion.

Losses are always a relief. They take a burden off me, make me feel more normal. If I win several tournaments in a row I get so confident I'm in a cloud. If I lose I go back to the dressing room and I'm no better nor worse than anyone else. A loss gets me eager again.

Ninety percent of my game is mental. It's my concentration that has gotten me this far. I won't even call a friend on the day of a match. I'm scared of disrupting my concentration. I don't allow any competition with tennis.