The Seattle Seahawks have put defensive end Branden Jackson on injured reserve eight days after he was briefly knocked unconscious during a scrimmage.

Coach Pete Carroll said doctors recommended Jackson not play this season after discovering a potentially dangerous condition with his spinal structure.

"He really came out of that episode OK, but just in the testing, it did show that he had a physical kind of a trait that's one to protect, so everybody has been convinced that the best thing for him to do is not to play this year," Carroll said. "I don't know if that's forever, but I do know for right now. He's not injured right now, but he's susceptible. It's similar to situations a couple of our other guys have had in the past, and we're erring on the side of long-term health and taking care of our guys. We had a good meeting with him and talked our way through it and all of that."

The former Seahawks Carroll was alluding to are safety Kam Chancellor and defensive end Cliff Avril, who each suffered career-ending neck injuries in 2017. Chancellor was left with spinal stenosis, or a narrowing of the spinal canal, as well as bone spurs.

"It's not the same thing as those guys, but it's similar," Carroll said. "Similar type of issues, so you know how those turned out."

Jackson was hurt when he knocked helmets with offensive tackle Cedric Ogbuehi. He was down for several minutes before members of the team's medical staff strapped him onto a backboard, removed the face mask from his helmet and loaded him into an ambulance.

Jackson had feeling and movement in his extremities at the time. He was taken to a local hospital as a precaution and released later that night. A source told ESPN that Jackson was able to drive himself home from the team's facility that night.

The Seahawks ended their scrimmage early when Jackson was injured.

Jackson has been back at the Seahawks' facility but has not been practicing. He wrote in an Instagram story last Sunday: "Thankx for all the thoughts and prayer. I'm Good Preciate the love."

Jackson is entering his fifth NFL season. He went undrafted out of Texas Tech in 2016, spending his rookie season with the Raiders and the past three with Seattle. He has been competing for a roster spot as one of the Seahawks' rotational defensive ends.

"He's a great team guy," Carroll said. "We love him on our team. He's got such spirit. He's got great versatility to his play, but he's just been such a great guy in this locker room that we're gonna miss him. I asked him to stay around as long as he wants to and be with us all along, and I hope he'll be able to do that."

Jackson was scheduled to make a non-guaranteed $2.133 million on the low tender as a restricted free agent this season before the Seahawks released him ahead of training camp and then re-signed him. Jackson's new deal is for one year and $1,047,500, according to a source. That includes a $75,000 signing bonus as the only guaranteed money and a $910,000 base salary. Jackson's deal counts as $877,500 against the salary cap.

The team signed defensive end Pita Taumoepenu in a corresponding move Sunday. Taumoepenu spent time on Seattle's practice squad last season.