I'm willing to bet there are plenty of injury/cancellation clauses in the contract.But it´s still risky for Discraft..10y is a long time....if he gets injured and can´t play anymore.
If paul can´t win anymore in a few years due to injury, he wont play
They didn't write him a $10 million dollar check and say "you're our disc golf slave for the next ten years."
It's still a job. There are things both parties will be responsible for doing over the next ten years and Paul will be paid according to a schedule, probably with performance bonuses when he wins.