Tagovailoa, who missed Weeks 5-6 due to a concussion, entered the league's concussion protocol on Dec. 26 after telling team doctors he felt concussion-like symptoms one day following the Dolphins' loss to the Packers.
Dolphins head coach Mike McDaniel announced Tagovailoa's concussion diagnosis on Wednesday, and Tagovailoa was ruled out of Week 17's matchup against the New England Patriots.
According to Fox's Jay Glazer, Miami head coach Mike McDaniel realized Tua was experiencing concussion-like symptoms after he couldn't remember some of the mistakes he had made during Sunday's loss to the Packers while the two were watching game tape together on Monday.
People on the internet seem to be conflicted on if Tua should even come back at all this season. Ultimately, Tua's ability to return will depend on his ability to progress through the five steps of the return-to-play protocol. Even then, the Dolphins may decide not to risk it with Tua, relying instead on Teddy Bridgewater if they make it to the postseason.