Allen Park — If the head injury suffered by Detroit Lions receiver Amon-Ra St. Brown on Sunday happened in Weeks 1-3, maybe he would have finished Sunday's game in Dallas. But under the NFL's amended concussion protocol, which took effect after the scary head injury suffered by Miami Dolphins quarterback Tua Tagovailoa in Week 4, Lions head coach Dan Campbell said St. Brown was prohibited from reentering the game.
The amended protocol states any players who show signs of ataxia — impaired balance or coordination from damaged brain or nerves — will not be allowed to return to the game and will be designated as having a concussion, regardless of whether they pass a concussion test in the medical tent.