Antonio Brown is back in the Raiders' camp after a two-week absence.
The four-time Pro Bowl wideout has been in a dispute with the NFL after his 10-year-old helmet was ruled illegal.
Brown said he is looking into a possible resolution with wearing an updated helmet of the same model.
Brown has participated in just one of the Oakland dozen practices because of extreme foot frostbite, which he suffered last month after a cryotherapy treatment.
The Raiders acquired Brown in March from the Steelers and signed him to a three-year contract for just more than 51-million dollars.