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.

I love hiking in the mountains in Aspen. Breathing the clean, fresh air is great. Plus, it gives me a cardiovascular workout and firms my legs.

The difference is almost all mental. The top players just hate to lose. I think that's the difference. A champion hates to lose even more than she loves to win.

I've had a lot of fear in my life, from fear of flying to fear of making a speech in front of a lot of people.

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.

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.

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.