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The NFL plans to make public the investigation into whether Tua Tagovailoa's concussion check-up during last Sunday's game against the Bills was properly administered.

Although the initial timeline meant the review would be completed within "a week or two" from now, Tagovailoa's concussion during Thursday night's game against the Bengals puts that timeline in question.

The review, which was initiated by the NFL Players Association and will be jointly administered with the league, will include interviews with several key people involved in the evaluation during the Bills game. Those people include, but are not limited to, the Dolphins team physician, the unaffiliated neurotrauma consultant, the certified athletic trainers, head coach Mike McDaniel and, of course Tagovailoa himself.

However, because Tagovailoa is in the concussion protocol, he won't be able to do an interview until he's cleared and healthy, according to multiple sources. It's a brain injury, so there's no timeline on when that might be.

On Saturday, the NFLPA exercised its option to terminate the UNC after discovering "several mistakes" made by the doctor in its view.

Last Sunday, Tagovailoa was allowed to return to the field after a hit sent him to the ground with the back of his head making contact with the turf. He got up, appeared to shake his head a few times and was wobbly on his feet. He was taken to the locker room for a concussion evaluation based off that gross motor instability.

Typically that sort of instability is considered a "no go," meaning the player cannot return to the field. The team physician, in consultation with the independent doctor, must determine the instability was not neurologically caused for the player to return. The doctors, according to many statements from league executives and McDaniel and Tagovailoa, determined the instability was caused by a back injury that had been suffered earlier in the game and was re-triggered on the hit.

Tagovailoa was cleared to return to the game. The Dolphins beat the Bills, and the following day Tagovailoa was evaluated again for any concussion symptoms. According to McDaniel, the quarterback didn't display any symptoms on Monday or throughout the week leading up to Thursday night's game in Cincinnati, though he was listed on the injury report all week with back and ankle injuries.

"So in terms of deciding whether or not to play a guy on a Thursday night game, I was concerned about his lower back and his ankle, and putting him in harm's way," McDaniel said Friday. "I have 100 percent conviction in our process regarding our players. This is a player-friendly organization that I make it very clear from the onset that my job as a coach is here for the players. I take that very serious and no one else in the building strays from that. So when I am talking about deciding whether or not to play, the only thing that would keep me from playing him would be something going against medical advice that would be just completely abstract on top of all that.

"I had no worries whatsoever. I'm in steady communication with this guy day-in and day-out. We're talking about high-level football conversations about progressions and defenses and recalling stuff from two weeks previous and then him having to reiterate a 15-word play call. All things, absolutely no signs. There was no medical indication, from all resources, that there was anything regarding the head."

The NFL has already sent all available video from the Buffalo game to the NFLPA for review. The standard report written by team medical staff has also been delivered, as well as reports from the unaffiliated neurotrauma consultants on both sidelines and the certified athletic trainers in the booth.

Once the interviews are complete, the NFL and NFLPA would conclude whether a violation was committed. A league source said that so far, every case in the past has seen both sides reach the same conclusion. If they don't, it would go to an independent arbitrator.

In 2017, the league fined the Seattle Seahawks $100,000 and required the coaching and medical staff to attend remedial training regarding the protocol when then-Seahawks quarterback Russell Wilson did not undergo a concussion evaluation after the referee determined one was warranted.