Wide receiver Antonio Brown’s tenure with the Raiders is off to a bizarre, shaky start.

The super-talented seven-time Pro Bowler, notorious for attracting controversy, may have outdone himself by declaring he won’t play football again if he can’t wear the helmet he wants, ESPN reported. Brown filed a grievance against the NFL on Friday and, according to ESPN, took part in a two-hour conference call with an independent arbitrator to argue his case.

Brown is protesting an NFL policy that doesn’t allow players to wear helmets that are not certified by National Operating Committee for Standards and Athletic Equipment (NOCSAE). Helmets older than 10 years cannot be certified, but Brown is apparently insisting on continuing to wear his decade-old model, the Schutt Air Advantage.

The 31-year-old Brown essentially cut off communication with the Raiders last week, when he left to seek treatment for his frostbitten feet — the result of a cryotherapy session that went horribly wrong. The team reportedly has no idea what the status of his injury is.

Raiders coaches and players are concerned that Brown’s frustration with the new helmet rule may be playing into his extended absence from training camp.

The Raiders said they are “aware and supportive of Antonio Brown, but [have] no further comment.” But NFL.com quoted a Raiders coach who referred to the helmet situation as “honestly the most insane thing I have ever heard. I don’t know why it’s so important to him. It doesn’t make any sense.”

The league and the NFL Players Association have tested helmets for safety since 2015 and officially began banning certain models last year. Star quarterbacks Tom Brady and Aaron Rodgers are among those affected by new enforcement. This season, a team with a player wearing a banned helmet would be subject to discipline. When the Raiders tried to get Brown to wear a compliant helmet model for OTAs, he pushed back.

Brown eventually agreed the following day, but went on to make two more attempts during training camp to wear his old helmet on the field, including once when he repainted his old helmet in Raiders colors. According to ESPN, Brown is convinced the alternative helmet interferes with his vision.

The Miami native has also reportedly shown up late to numerous meetings and is blatantly distracted during them. It seems a continuation of Brown’s downward spiral with the Steelers. Brown requested a trade this past offseason after he was benched toward the end of last season as a result of internal turmoil that included skipping practices and an argument with quarterback Ben Roethlisberger. Now, the antics seem to have spilled over to his new team.

If Brown retires, he would forfeit at least $30 million in guaranteed money. Hard knocks, indeed.