Dolphins QB Tua Tagovailoa Out Of Sunday's Game, Still In Concussion Protocol

Tua Tagovailoa won't be under center when the Dolphins take on the Jets this Sunday, the team just announced, after the 24-year-old QB sustained a brutal hit to the head on Thursday Night Football.

Mike McDaniel, the Fins' first-year head coach, told media Monday Tua was still in concussion protocol and was out for the week 5 clash with the division rival Jets.

Of course, Tagovailoa was on the receiving end of two brutal hits within a five-day period.

The first came during Sunday's week 3 game against the Bills, when Tua was slammed to the ground, appearing to hit his head. He attempted to stand up, but wobbled, falling to the ground. Many experts say it was a clear-cut sign of a concussion ... but team officials insisted it was actually a back injury.

Then, just days later during "Thursday Night Football," a nationally televised game against the Bengals, Tua again took a huge hit to the head. The former 5th overall pick lay on the ground, hands "postured," unconscious. Medical staff rushed out, removed Tua's facemask, put him on a stretcher, and took him to the hospital.

Tagovailoa was released later that night ... and flew back to Miami with his teammates on the team plane.

We spoke to traumatic brain injury expert, Chris Nowinski, last week after the second injury ... and the former football player and WWE Superstar told us Tua shouldn't play again this season, and should consider never playing for the Dolphins again after the handling of the injuries.

It's not just Nowinski who believes the situation was handled inappropriately ... in fact, the NFL-NFLPA are conducting a joint investigation aimed at looking at what went down behind the scenes with Tua's injuries.

Coach McDaniel was asked about the inquiry ... and he says the organization will be an open book.