Clarett was not a party to nor were interests represented in the collective bargaining agreement. That this was the best argument the NFL could present indicates the weakness of its case. Whether this decision is best for the NFL or college footbal is not the point; Clarett's rights are.
Is the entire concept of having a draft even legal? Shouldn't a player have the right to sign with whatever team he wants (provided they want him), instead of having his employer dictated to him by the league?
And how are his rights being violated by being denied a job that he's not qualified for? The rules are the rules. If they let him play then they also have to let 20 year olds be elected president. Same deal. He's not old enough (mature) yet for that game.
(Recognize that not all Calvinists will be Christians in glory.
And there's absolutely nothing they can do about it either according to Calvinist thought)