There are some guys you have problems beating because of their style - I always had difficulties with guys like Michael Chang and Andre Agassi because their returns were so good and they played so well in defence.

Suddenly in the end when it's over, you feel a big weight on your shoulders. That's the role of the captain. Unfortunately, it's sometimes like that in sport.

I retired because I had a knee injury, my cartilage was wearing out, it was painful and I couldn't put in the four hours of practice each day that I needed to.

More than specific memories of achievements, for me I remember the feeling you get when you were just at your very best - when you felt like you were floating across the court and could put the ball wherever you wanted.

It's better to have done because then you know what the player is going through and you understand the pressure, but then on the other hand I know a lot of people that were good players but not good coaches, and vice versa.

It's a tough world out there and all the guys are fighting hard and the competition is really tough.

You should just enjoy it, but as soon as you decide that it is going to be your career, no matter whether you want to be a doctor or an architect or anything else, you need to work 5 hours a day.