The 49ers fear safety George Odum will miss the rest of the season with a torn biceps.
Odum will undergo an MRI on Friday to determine the severity.
“We’ll look into him tomorrow, but most likely tore it,” Shanahan told reporters Thursday night, via David Bonilla of 49erswebzone.com. “It usually is season-ending, but you never know if he can have a chance to come back later. We’ll have to look into that tomorrow.”
The 49ers lost All-Pro safety Talanoa Hufanga to a torn ACL last week, and now face the prospect of playing the rest of the season without Odum.
The core special teams player had played 72 percent of the team’s special teams snaps this season before Thursday. He was injured in the second quarter when Seahawks returner DeeJay Dallas mishandled a kickoff, and Odum scrambled for the loose ball.
The 49ers will have to address the safety position, adding a player from another team’s practice squad or finding a free agent.
“Yeah, we’re going to have to do something because we were having to do some stuff anyways as it was,” Shanahan said.
Odum has 12 tackles this season.
,"He’s been unbelievable,” Shanahan said. “He’s been one of the best special teams players in the league here, and he’s a very good safety for us, too. So we’ve been thin there with the depth, and losing him is a big deal. We’ll have to see what our options are here, though, when we get in.”