First it was Antonio Brown’s feet that made news. Now it’s his head.

Brown, the star receiver who joined the Raiders this year, appears to have lost an ongoing dispute about his helmet. In short, Brown prefers to wear the make of helmet he has been wearing for years, but the N.F.L. says that type, now 10 years old, is no longer approved.

On Monday an arbitrator ruled against Brown’s grievance.

“While I disagree with the arbitrator’s decision,” Brown wrote on Instagram, “I’m working on getting back to full health and looking forward to rejoining my teammates on the field. I’m excited about this season appreciate all the concerns about my feet.”

For those who missed it, the health issue Brown referred to is blistering and peeling of his feet, which has kept him out of training camp. It emerged last week that the injury was frostbite, caused by a trip to a cryogenic therapy chamber.