Tagovailoa briefly left Sunday's win over the Buffalo Bills and was evaluated for a concussion after hitting the back of his head on the ground during the second quarter. He stumbled while trying to jog back to the huddle after the play, prompting the Dolphins to evaluate him for a concussion on the sideline and ultimately in the locker room.
After the game, both McDaniel and Tagovailoa said it was the quarterback's back that caused him to stumble, not a head injury. Tagovailoa said he felt like he "hyperextended" his back earlier in the game on a designed quarterback sneak, and it flared up late in the second quarter.
Tagovailoa said he passed the league-mandated concussion protocol at halftime and was allowed to return to the game.
Despite Tagovailoa's and McDaniel's comments, the NFL Players Association told the NFL it wanted a review of the league's concussion protocol because of Tagovailoa's quick return to the game. Speaking to reporters Monday afternoon, McDaniel said the Dolphins will comply with any league investigation and insisted that he would not have allowed his quarterback to be put in harm's way "if there were any red flags."
"The one thing that our players know more than anybody is there's certain things that I'm very sensitive to -- I've been called emotional from time to time -- and one of those things is player health," he said. "I don't mess around with that at all. Tua was pretty annoyed with me in the game because he knew what hurt and didn't understand why people kept talking to him about what we were talking to him about. I think watching replays, he probably could.
"The pillar of importance for all of it is player safety -- that's why the protocols are in place. We're happy to comply and I feel fine about that whole process, really."
McDaniel also said Monday that Tagovailoa was sore, as expected, and dealing with ankle soreness as well as back soreness from the game.
He did not commit one way or the other as far as Tagovailoa's availability for Thursday's game but did say they're still acquiring information and will be ready for any scenario.
"It's my first time on a Thursday night game with Tua, so I don't assume anything," he said. "As far as me being able to access my crystal ball -- it's broken right now. That's one of the reasons why you have a roster of capable people, that's why we brought Teddy [Bridgewater] here and drafted Skylar [Thompson]. You have to be ready for these type of adjustments. Just like Teddy was ready in the game, we'll be ready for whatever we have to deal with moving forward.
"These Thursday night games, you just try to do the best you can. We're trying to get information as fast as possible and we'll be working fluidly from that. Right now, not just Tua, but there's a lot of players that we'll be adjusting to on the fly, seeing if they can turn it around and give a healthy outing on Thursday."
The Dolphins did not practice on Monday but estimated that Tagovailoa would not have participated in their injury report.
Tagovailoa is currently the NFL's second-leading passer and ranks second in yards per attempts and first in QBR. He finished Sunday's game with 186 passing yards and a touchdown on 13-of-17 passing.