If that athlete isn't available ... then these companies look for athletes who have the chance to be the next big thing. In Michelle's case, her youth plays very much to her advantage.

Martina had just turned 22 when injuries forced her to stop. Now, at the age of 25, with several operations behind her, she is looking forward to the challenge of playing events.

Part of her payment is based on the hope and expectation that she is going to become very good very quickly. The other factor is the platform in which she plays is healthy and growing.