The thing about tennis is if you stay off for two weeks, or just for three days, you can lose your rhythm quickly. So it's just a question of constant diligence and vigilance.

Everybody's got their problems. The important thing is not to complain about it.

For years I felt that I didn't have enough stamina and then, four years ago, I felt like I was not getting enough air but I was diagnosed with exercise-induced asthma. The medicine for asthma never worked.

So what if you fail? At least you'll know what not to do when you try again.

I don't come to tournaments to make friends, to go to parties, to hold conversations. I come to be the best, and I'm not mean and cruel and dirty.

There have been many frustrating games. I don't there's going to be another one that isn't frustrating. That happens, but that's sport. Otherwise why would there be so much glory in victory.

Some people say I have attitude - maybe I do...but I think you have to.