Have you ever been amazed by the skills of your favourite tennis stars and wondered just how they do it?

We asked tennis coach Dan Thorp to analyse four of the world's top players and tell us exactly what to look out for.

Dan has scrutinised the games of Roger Federer, Maria Sharapova, Andy Roddick and Serena Williams.

For each player, he's picked one aspect of their game in which they really excel and explained why it makes them so special.

So click on the links below to find out exactly what qualities make a tennis star shine!

Introduction

Roger Federer

Maria Sharapova

Andy Roddick

Serena Williams