Minnesota Vikings star running back Adrian Peterson's appeal of his suspension from the NFL for beating his son has been denied by the arbitrator named by Commissioner Roger Goodell to handle the matter, the league said.
Arbitrator Harold Henderson said in his ruling that Peterson, the 2012 NFL Most Valuable Player, "has not demonstrated that the process and procedures surrounding his discipline were not fair and consistent".
Henderson added that Peterson "was afforded all the protections and rights to which he is entitled, and I find no basis to vacate or reduce the discipline".
Henderson is a former NFL executive vice president of labor relations who has heard 87 appeals since 2008 involving personal conduct and drug issues.
Peterson, who played in only one game this season before being taken placed on the commissioner's "exempt list", is expected to appeal the decision in federal court.
Peterson, 29, pleaded no contest on November 4 to misdemeanor reckless assault of his four-year-old son, allowing him to avoid a felony child-abuse conviction. After Peterson's plea, Goodell suspended Peterson until at least April 15 for violating the NFL personal conduct policy.
He was arrested in September on a felony child abuse charge for disciplining his son by repeatedly striking him with a thin tree branch called a switch.
The players' union condemned the arbitrator's decision.