NFL Chief Medical Officer Dr. Allen Sills said on the NFL Network Friday that Miami Dolphins quarterback Tua Tagovailoa was checked for concussion symptoms every day this week.

Tagovailoa, 24, left Thursday night's 27-15 loss against the Cincinnati Bengals in the second quarter after appearing to be knocked unconscious following a sack. He was taken off the field on a stretcher and taken to a local hospital with head and neck injuries, though he was released from the hospital and flew back with the team to South Florida.

Tagovailoa was being monitored ahead of Thursday's game after suffering an injury last weekend and returning to the game. Following a hit in a win over the Buffalo Bills, Tagovailoa stumbled after he got back to his feet and he was listed as questionable to return to that game with a head injury.

However, after undergoing tests, the team determined a back injury, not a head injury, had caused the stumble, and he was permitted to return to the game.

The NFLPA promptly opened an investigation into the Dolphins' handling of that injury. And after Tagovailoa's injury on Thursday night, the NFLPA released the following statement:

NFLPA president JC Tretter followed up with a statement of his own:

Sills, meanwhile, also made an appearance on CNN and offered more information on the situation and the NFL's concussion protocols:

It remains unclear when, or if, Tagovailoa will play again this season.

"I'm not even thinking about timetables as a player," head coach Mike McDaniel told reporters when asked if the Dolphins were considering an IR stint for Tagovailoa. "It's about Tua as a person. We're just worried about him getting healthy and getting all of the testing done. We'll cross the bridge on timetables."

"You wanna win the game but obviously you wanna make sure that your brother is all right," wide receiver Tyreek Hill added on Thursday night, saying players had been asking for updates on Tagovailoa's during the second half. "Football is just our part-time job, but that brotherhood is something that'll last forever."