You gave a six-year-old boy his Laker dream And I'll always love you for it. But I can't love you obsessively for much longer. This season is all I have left to give. My heart can take the pounding My mind can handle the grind But my body knows it's time to say goodbye.

No, I think they were two totally different careers, because when I was acting, I was always impersonating different people, so it was never me—it was never myself. When I started to sing, I suddenly felt naked. I mean, I knew that was going to happen, because that’s the reason why I couldn’t do it before—when I was a teenager, I just couldn’t play in front of anyone at all—it was impossible, my hands started to shake, my voice was gone, and I was so self-conscious of what people would think about what I was doing. Because I didn’t know how to play songs that anybody knew—all I knew how to play were my own songs, and so I had this feeling of having my own chords and my own things that weren’t—I was afraid of being judged as doing nonsense music. But then maybe what the acting did to me was that I got more courage to do what I really wanted to do, even though I had all these fears that were still inside me.

The task of finally making a decision to hang up my racquet felt a lot more difficult than winning seven matches in a row in the Australian heat. It took me several agonizing months to finally come to the decision that my chronic injuries will never again let me be the tennis player that I can be. Walking away from the sport, effective immediately, is the right decision for me and my family.

As many of you know, the past three years have presented me with challenges in the form of injuries and surgeries. I've worked hard to return to full competitive form. But I also know my body's capacities and limits, and its message to me lately has been clear. I am 41 years old. I have played more than 1,500 matches over 24 years. Tennis has treated me more generously than I ever would have dreamt, and now I must recognize when it is time to end my competitive career.

There's still much to do, and I'm not slowing down.

Family is the center of my life. Without a doubt, the saddest day of my life was July 13, 1991, when I lost my eldest son, Harrison, in a car accident.

We have made many investments in our history. Not all have succeeded. As entrepreneurs willing to take some risk, we have made many mistakes. But when we are successful, we leave the company better than we found it.

I’m very proud of that and I started a drug and substance abuse program in middle schools in New York to help the worst performing schools.

My father tried to make me think twice. "Son, calm down," he said. "Stick it out."

You have to do something like that to get rid of the tension, take your mind off what you are doing.