Case study based on "NFL Contract for Ricky Williams"

1. Does this case involve a duty of care issue or a duty of loyalty issue?
2. Does it make a difference if the agent fully informs the player of all the risks associated with signing a contract with little to no guaranteed money, and the player decides to sign it anyway?
3. Is it ever ok to lie during negotiations? Can failing to tell the "whole truth" be part of a negotiating strategy? Should an agent ever represent that he or she has an offer from another club when in fact this is not true, solely to improve the client's negotiating position?
4. Under what circumstances should an agent advise his client to "hold out"? If a player is legally bound under a contract to play, does an agent engage in an unethical act by advising the player to hold out for more money notwithstanding the player's contractual obligations? Would the agent be advising the player to breach his or her contract?

Use link for reference - https://fivethirtyeight.com/features/ricky-williams-awful-nfl-contract-never-gave-him-a-chance/