In tennis, you can make a couple of mistakes and still win. Not in golf. I played three rounds in that Tahoe event, and I was drained. Mentally, not physically.

My goal one day is to be in the same sentence as Rod Laver and Ken Rosewall.

For so long people have just taken what I do for granted. It is not easy to do year-in, year-out, to win Grand Slams and be No. 1.

The difference of great players is at a certain point in a match they raise their level of play and maintain it. Lesser players play great for a set, but then less.

Most of the time after the US Open, it is kind of like you are trying to finish strong. But to do it five years and maybe six is something that has never been done before, so it is a huge challenge.

There is no doubt about how hard it is to stay on top in any sport, but to do it in an individual sport for the majority of your career, it is not easy.

Tennis obviously isn't as popular as baseball in the States.