The Houston Texans’ handling of an injury to quarterback Tom Savage was called into question after video showed him striking his head against the ground and shaking as he lay disoriented on the field.

Savage, who also appeared to spit up blood, came out of the game and entered concussion protocol but initially returned to the field, replacing T.J. Yates on the team’s next possession.

His appearance was brief, though. After the Texans went three-and-out (a 1-yard loss by Lamar Miller and two incompletions), he headed to the locker room and was declared out shortly after halftime.

He is now the sixth Texans player dealing with concussions and on Monday morning the Texans announced that Yates would start Sunday against the Jaguars. Tight ends Ryan Griffin and C.J. Fiedorowicz will miss the rest of the season because of concussions; running back Alfred Blue, wide receiver Braxton Miller and linebacker Jelani Jenkins missed the San Francisco game.

Coach Bill O’Brien opened his postgame news conference with a statement in which he said that, in his 25 years of coaching, nothing has been more important than the health of his players. “I love our players,” he said and went on to explain that Savage said he was evaluated and cleared to return, but that he underwent another evaluation after he returned because “because of what they saw.” O’Brien did not elaborate on what that might have meant.

“They try to make the best decision for the player,” O’Brien said. “Whatever they see and the testing that they do they try to make the best decision with the player and they weren’t satisfied with the results of the second test so they decided to pull him, and that’s when he went into the locker room.”

Asked if he was concerned that Savage was allowed to return, O’Brien pointed out that he doesn’t control that and added that he would have kept Savage out if he had seen the video.

“They just come to me and that’s kind of where that’s at,” he said. “I don’t have anything to do with that. All I do is coach.”

Because he is in the concussion protocol, Savage did not speak with reporters after Houston’s loss, but Chris Nowinski, the founder of the Concussion Legacy Foundation and Boston University’s CTE Center, angrily tweeted that he was “disgusted” that Savage returned. “I would not let my worst enemy go through the 2017 #NFL sideline concussion protocol.” He continued that “the protocol is breached weekly. No one is punished. We pretend it didn’t happen.”

As of the middle of November, the NFL said it had conducted 379 concussion evaluations (including preseason games). The NFL and the NFL Players Association are reviewing the Savage case; the two have a policy in place to jointly investigate these cases and determine if there was a violation. If warranted, discipline can be handed down.

“Those are just the amount of times that people were screened,” Dr. Allen Sills, the NFL’s Chief Medical Office, said in a briefing Nov. 14. “And to be clear, we want that number to remain high. We want to have a high bar set for screening. Our motto to all of our personnel on game day is if you see something, say something. We want anyone who has a concern to point it out, we want to be very aggressive in our screening.”

Teammates said that Savage seemed fine and coherent, but concussions can be difficult to assess because symptoms can develop later. As Savage showed, NFL players can be their worst enemies. They do not want to come out of games. Ever.

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