I am so sorry for you and for your son. I think that what you need to do is to go and see a personal injury attorneyin your area on the matter as soon as you can.  What you are claiming is really a speculative thing. For all you know he could have had an "off day" on the date of the original try outs even if the car accident had not taken place.  But I would not absolutely discount the issue, especially when you are negotiating a settlement. It just may be very hard for you to prove.  It is best to speak with someone sooner rather than later to get advice is you insist on negotiating yourself. Good luck to you an to your son.