San Francisco coach Kyle Shanahan said linebacker De’Vondre Campbell will not be part of the 49ers after he refused to play in a game after losing his starting job.

Shanahan said the team is still working on ways to deal with Campbell, who was walking into the locker room in the middle of a 12-6 loss to the Los Angeles Rams on Thursday night when he refused to come into the game.

“His actions from the game are not something you can do to your team or your teammates and still expect to be part of our team,” Shanahan said Friday. “We are currently working on the semantics, but we will handle the situation appropriately.”

Shanahan said Campbell will not be part of the team for the final three weeks. Under the collective bargaining agreement, teams have the option to suspend players for up to four games without pay if they have a negative impact on the team. The Niners could also simply waive Campbell entirely, which would allow him to potentially be claimed or signed by another team.

Campbell signed a one-year, $5 million contract with San Francisco in March.

Campbell had started 12 of the first 13 games of the season and played 90% of the defensive snaps for the 49ers, but was benched Thursday night after Dre Greenlaw returned for his first game since tearing his left Achilles tendon in last season’s Super Bowl .

When the 49ers wanted to bring Campbell into the game in the third quarter because Greenlaw was sidelined with Achilles tendon pain, Campbell declined, something Shanahan said had never happened to him in his time as a head coach or assistant in the NFL. Shanahan said Friday that he received no explanation from Campbell as to why he didn’t play.

Campbell then left the field with a towel over his head and went to the locker room before the game with the Rams ended, which nearly ended the 49ers’ playoff hopes. Shanahan said he didn’t send Campbell to the locker room and didn’t know why he left the field.

“When I found out he wasn’t playing, I reached out to people we could count on,” he said.

Campbell’s decision sparked anger and confusion among his teammates.

“He’s a professional,” cornerback Charvarius Ward said after the game. “He’s been playing for a long time. If he didn’t want to play, he shouldn’t have dressed up. He could have told them before the game. I think that was selfish. It definitely hurt the team. Dre went down and we needed a linebacker. … The fact that he’s doing that is, in my opinion, complete nonsense. He will probably be circumcised soon.”

Ward is one of several 49ers who have suffered injuries or personal tragedies during a difficult season for San Francisco. Ward’s 1-year-old daughter died on Oct. 28, but he has returned and played the last three games for San Francisco.

Tight end George Kittle called Campbell’s actions “stupid” and “immature.”

“It’s a person making a selfish decision,” Kittle said. “I’ve never been around anyone who has ever done that and I hope I’m never around anyone who does it again.”

Campbell, 31, signed with San Francisco in the offseason after being released by Green Bay in March. He had been an All-Pro for the Packers in 2021, but his performance declined over the last two seasons in Green Bay.

That led to Campbell complaining on social media that he had been abused by Green Bay. He expressed excitement about being on a new team, but never reached his All-Pro level again. Campbell had some bright moments in San Francisco this season, but often struggled with tackling and coverage.