Imagine that you never even made the team in the first place because you were born with one leg longer than the other, too short, were in a car accident and had brain damage, etc. Imagine that you still thought that success was only possible if you were a successful athlete. Now that you've imagined this person - compare yourself to him in your mind. Feel grateful for what you have. What you are doing is something that many people do which is to always compare yourself to persons who have more of something than you do and feel a failure as a result.
Millionaires compare themselves to billionaires and feel inadequate.
Beautiful women compare themselves to models on magazine covers and feel inadequate. You have to reset your idea of success to an attainable level - something you are capable of accomplishing. You need to cultivate an attitude of gratitude. You need to feel adequate as you are because you understand inside that you are good enough . Until you do this you will be a slave to your feelings of insecurity.