NFL and players agree to enhanced concussion protocols

A joint statement from the two parties on Saturday said ataxia - which includes abnormal balance, motor coordination or "dysfunctional speech" - would be added as a "no-go" symptom. Players diagnosed with ataxia during a game will not be allowed to return to the field.

Tagovailoa was carried off the field last week when his head slammed into the turf as he took a sack during a game against the Cincinnati Bengals.

Fans and armchair experts alike questioned why he was allowed to play against the Bengals as four days prior he looked disoriented after hitting his head to the ground during a game against the Buffalo Bills.

Miami coach Mike McDaniel defended his decision to allow Tagovailoa to play against the Bengals, saying "several layers of medical professionals" had cleared the quarterback.

The NFLPA initiated an investigation into the incident.

"While the investigation determined that the team medical staff and unaffiliated medical professionals followed the steps of the Protocol as written, the NFL and NFLPA agree that the outcome in this case is not what was intended when the Protocols were drafted," the joint statement read.

Tagovailoa will not travel for his team's Sunday game against the New York Jets.