Here is a copy of the OU student-athlete handbook. It is in essence the guideline for required student-athlete behavior by members of an athletic team and the receipt of financial aid. The meaty part relating to student behavior is contain primarily on pages 73-86.
Joining a team means compliance to these rules and constitutes a contract between the school, the team and the student athlete. It specifically states on page 76 that:
• Respect coaching decisions - voice concerns privately following team
procedures; and
• Exhibit dignity in manner and dress while representing OU both on and off
the field.
It further states on page 74:
At the beginning of each academic year, your coach will provide rules specific to your program. These rules are supplemental to and do not supersede the Student-Athlete Code of Conduct, Regent’s Policies, the University of Oklahoma Student Code of Responsibility and Conduct, as well as Big 12 Conference and NCAA policies and procedures. Failure to follow all applicable guidelines may result in termination of your status as a student-athlete and cancellation or reduction of your financial aid.
In general term if there is an unambiguous offer to join the team and abide by the team rules and an unambiguous acceptance to join the team and abide by the team rules you have consideration on the part of both parties and an implied contract enforceable by law.
Therefore if a player joins a team with rules concerning how they represent the team during the national anthem they have waived the right to protest during the national anthem without being subject to discipline for violating team rules.
Of course should they be disciplined for protesting in uniform they definitely have the right to appeal per the appeal process stated in the student-athlete handbook.
http://www.soonersports.com/pdf9/3751217.pdf?DB_OEM_ID=31000
