Just because a player doesn't have a contract doesn't mean they can't get a contract. It means they haven't found a contract that they want to sign right now. Think about it. If you think that you ranking is going to go up a lot and your current sponsor is offering peanuts because your ranking is currently well below what you believe it will soon be, why would you sign for those peanuts? Buy some spraypaint, wait until your ranking is way higher then reapproach the racquet company.