Miami Dolphins quarterback Tua Tagovailoa was ruled out of Thursday night’s game with the Buffalo Bills because of a concussion after colliding with defensive back Damar Hamlin and hitting the back of his head against the turf.

Tagovailoa, who has a history of dealing with head injuries, remained down for about two minutes before getting to his feet and walking to the sideline after the play in the third quarter. He made his way to the tunnel not long afterward, looking into the stands, appeared to smile and departed for the locker room.

The Dolphins needed almost no time before announcing it was a concussion.

Tagovailoa, who sustained multiple concussions his first three NFL seasons, positioned himself for a big pay bump with an injury-free and productive 2023. He threw for 29 touchdowns and a league-best 4,624 yards.

He signed a four-year, $212 million extension before this season and was the NFL’s leading passer in Week 1 this season. Tagovailoa left the game with the Dolphins trailing 31-10, which held as the final score. 

Tagovailoa was hurt on a fourth-down keeper with about 4:30 left in the third. He went straight ahead into Hamlin and did not slide, leading with his right shoulder instead.

He wound up on his back, both his hands in the air and Bills players immediately pointed at Tagovailoa as if to suggest there was an injury. Dolphins center Aaron Brewer quickly did the same, waving to the sideline.

Tagovailoa eventually got to his feet. Dolphins coach Mike McDaniel grabbed the side of his quarterback’s head and gave him a kiss on the cheek as Tagovailoa departed. Skylar Thompson came into the game to take Tagovailoa’s spot.

Hamlin was the player who suffered a cardiac arrest after making a tackle during a Monday night game in January 2023 at Cincinnati, causing the NFL to suspend a pivotal game that quickly lost significance in the aftermath of a scary scene that unfolded in front of a national television audience.

Tagovailoa’s history with concussions — and how he has since worked to avoid them — is a huge part of the story of his career, and now comes to the forefront once again.

He had at least two concussions during the 2022 season. He was hurt in a Week 3 game against Buffalo and cleared concussion protocol, though he appeared disoriented on that play but returned to the game.

The NFL later changed its concussion protocol to mandate that if a player shows possible concussion symptoms — including a lack of balance or stability — he must sit out the rest of the game.

Less than a week later, in a Thursday night game at Cincinnati, Tagovailoa was concussed on a scary hit that briefly knocked him unconscious and led to him being taken off the field on a stretcher.

His second known concussion of that season came in a December game against Green Bay, and he didn’t play for the rest of the 2022 season.

Going into last season, Tagovailoa added muscle and spent time studying jiu-jitsu in an effort to learn how to fall more safely and try to protect himself against further injury.