(AP/WJW) — The NFL Players Association has fired the unaffiliated neurotrauma consultant who evaluated Miami Dolphins quarterback Tua Tagovailoa after he stumbled off the field against Buffalo last weekend, a person familiar with the decision told The Associated Press over the weekend.

The person who confirmed the firing, which was first reported by Pro Football Talk, spoke to the AP on condition of anonymity because a joint review by the NFL and its players’ union into Tagovailoa’s quick return to Sunday’s game is ongoing.

There are three unaffiliated neurotrauma consultants at each game. They are jointly paid by the league and the players’ union to work with team physicians to diagnose concussions. The NFLPA is exercising its right to terminate the UNC directly involved in the decision to clear Tagovailoa, who sustained a concussion following a frightening hit just four days later at Cincinnati on Thursday night.

Tagovailoa initially seemed to exhibit concussion symptoms after the hit to his head during the home game against Buffalo, but he was cleared by a team physician and UNC to return. He and the team later explained his legs were wobbly because of a back injury.

After the hit on Thursday, when 6-foot-3, 340-pound Bengals defensive tackle Josh Tupou slammed him backward into the turf, Tagovailoa’s hands froze up and his fingers flexed awkwardly in front of his facemask for several seconds as he laid on the turf in Cincinnati. He remained on the ground for several minutes until he was taken away on a stretcher and sent to a hospital. He was released from the hospital and flew home with the team hours later.

Concussions are common in the NFL, especially when a player is thrown to the ground by a man Tupou’s size and his head hits the turf.

The NFL and the players association issued this joint statement on Saturday:

The joint NFL-NFLPA investigation into the application of the Concussion Protocol involving Miami Dolphins’ quarterback Tua Tagovailoa remains ongoing. Therefore, we have not made any conclusions about medical errors or protocol violations. 

The NFL and the NFLPA agree that modifications to the Concussion Protocol are needed to enhance player safety. The NFLPA’s Mackey-White Health & Safety Committee and the NFL’s Head Neck and Spine Committee have already begun conversations around the use of the term “Gross Motor Instability” and we anticipate changes to the protocol being made in the coming days based on what has been learned thus far in the review process.

The NFL and NFLPA share a strong appreciation for the unaffiliated neurotrauma consultants who contribute their time and expertise to our game solely to advance player safety. This program has made our game safer for the athletes who play it for the past twelve seasons.

Dolphins coach Mike McDaniel said Friday there is no timetable for Tagovailoa’s return.