(AP) — The players’ union has asked NFL Commissioner Roger Goodell to recuse himself from the appeal hearing for Tom Brady in the deflated footballs case.

The NFL Players Association formally made the request Tuesday, citing “a process that has contained procedural violations of our collective bargaining agreement.”

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The union calls Goodell a “central witness in the appeal hearing,” adding he is not impartial. The NFLPA is seeking a neutral party to serve as an arbitrator.

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Brady was suspended for the first four games of the 2015 season for his role in the use of underinflated footballs in the AFC championship game.

The league says it will not comment on the union’s request.

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