Oakland Raiders wide receiver Amari Cooper went to the locker room after taking a helmet-to-helmet hit from Seattle Seahawks safety Bradley McDougald.
Oakland announced that Cooper was being evaluated for a concussion, and the receiver was later ruled out for the rest of the game.
The fourth-year wideout appeared to be unconscious for several moments before walking off the field.
Reports surfaced earlier Sunday that the Raiders were shopping Cooper and teammate Karl Joseph.
The two-time Pro Bowler has 22 receptions for 280 yards and one touchdown through five contests in 2018.