HOUSTON — Texans coach Bill O'Brien said Monday that he wouldn't have let Tom Savage re-enter Sunday's game after an alarming hit that gave him a concussion and left the quarterback's hands shaking if he had seen the video of the hit.

Savage was injured with about nine minutes remaining in the second quarter of Houston's 26-16 loss to San Francisco when he was driven to the ground on a hit by Elvis Dumervil.

Replays showed Savage looking dazed after his head hit the ground with both of his arms shaking and lifted upward.

He was taken to the medical tent where he stayed for less than three minutes before returning to the bench and going back in for the next series.

Savage threw two incompletions on that drive, and Houston's team doctor approached him after he returned to the sideline at the end of that possession.

He was then evaluated again and taken to the locker room after it was determined that he did have a concussion.

"There's no video on the sideline. All there are are tablets," O'Brien said. "There's no video, there's nothing like that. With benefit of seeing the video ... (and) the care for the player, I would've never let that player back in the game, and I don't believe that (trainer) Geoff Kaplan would've allowed that player back in the game. I don't have benefit of the video. I did not see anything."

Also on Monday an NFL spokesman said the league is looking into whether concussion protocol was properly followed after Savage was injured.

League spokesman Joe Lockhart said the NFL and the players' association "together will conduct a thorough review of the incident focused on whether the protocol was properly followed, but we're also continuing looking at the protocol to look for ways to improve and strengthen it."

O'Brien talked at length about the way Savage's concussion was handled and explained the series of events that led to him leaving the game. He shared what he was told after the second evaluation.

"They came to me, they were not satisfied with his answers to the questions that they were asking him, and they pulled him from the game," O'Brien said.

The hit occurred in the end zone and O'Brien said he was near the 50-yard line when it happened and that he did not see it live. He said he assumed Savage got hit on the play, which was an incomplete pass, but didn't know for sure until later.

"At no point in time is there anything more important to me than the safety of our players," he said. "I love our players and I care about them and I cannot stand when players get injured. Again, with benefit of seeing the video that people are seeing, I would've never put him back in the game."

O'Brien didn't have an update on Savage's condition on Monday, but said that he expects backup T.J. Yates to start on Sunday against the Jaguars. Yates took over against the 49ers after Savage was injured for his first game action since 2015.

Savage and Yates are the only quarterbacks on Houston's roster so the team will likely need to sign another quarterback to back up Yates on Sunday.

While O'Brien discussed what happened on Sunday, he wouldn't share his feelings about how the process of evaluating players for concussions could be improved or if he finds it worrisome that the procedure allowed Savage to return when he had a concussion.

"I think these are great questions, but I'm just here to tell you what my role is in it and I think those are questions for someone else. I really do," he said.

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AP Pro Football Writer Barry Wilner contributed to this report.

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