The Houston Texans were criticized after quarterback Tom Savage was allowed to re-enter Sunday’s game against the San Francisco 49ers after possibly sustaining concussion.

Savage got injured nine minutes into the second quarter. He was on the ground when both arms appeared to twitch.

Savage was taken to a medical tent and returned to the bench. Three minutes later, he went back into the field for the next series.

Savage later tried to enter the game again, but a team official kept him away, dragging his jersey and pulling him away from the field. The player was seen arguing with the official and the team’s trainer before being escorted to the locker room.

The incident raised concerns about the NFL’s procedures for evaluating such injuries and ensuring the wellbeing of the players.

Many NFL fans criticized the team for letting Savage back on the field after the hit.

“Tom Savage was twitching after that hit. May not be for 20 years, but it's stuff like that'll be the eventual downfall of the NFL,” one Twitter user posted.

Chris Nowinsk, a critic of the NFL’s handling of concussions, tweeted,  “Disgusted that the Houston Texans allowed Tom Savage to return to the game after two plays after showing these horrifying concussion signs (is that a seizure?) after a head impact.”

Coach Bill O'Brien defended the decision to let Savage back in the game after the first evaluation, saying the player was cleared to return following initial evaluation for a concussion but was later sent to the locker room “because of what they saw.”

"They try to make the best decision for the player," the coach 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."

When asked if it is troublesome that Savage was allowed to re-enter the game after the concussion, O’Brien said he does not “have anything to do with that,” adding that “All I do is coach."

Teammates also said that there was nothing different about Savage after the hit. T.J. Yates, who took over for him, said "When he got back to the sideline he seemed fine and coherent.”

The 49ers won the game 26-16.

The Associated Press contributed to this report.