I feel like when I'm match tough and match hard and played a lot of matches I got that competitive winning spirit going and I can get on some rolls like I did last year. I won San Jose, Indian Wells and made the semifinals in Miami so it can happen for me.

I am two different people. What you see on the court is just natural for me. I wear my heart on my sleeve. I have always said 'C'mon' purely to fire myself up. Off the court, I am a lot shyer. I stick to my team and my family and people I trust.

I'm not to eager to play tennis in my spare time. I'm more interested in doing gym work and stuff like that. We have a lot of schools and courts around where I live, so if I really want to play I don't need to go too far.

I don't know. Haven't I always been mature?

My video game character is a bit better looking than me, actually. I don't think he has to worry about his hair getting messed up.

That's when you've got to grit your teeth and hang in there and try and find a way to win when you're not playing your best tennis - that's what I can be proud of

I was lucky enough to win the Davis Cup in my first year in 1999. I won my first slam at the U.S. Open in 2001 and became world No. 1 later that year. By the age of 20, I'd done it all.