San Francisco safety Antoine Bethea was placed on season-ending injured reserve Friday with a shoulder injury suffered in Thursday night's 20-3 loss to Seattle.
The move cleared room on the 53-man roster for wide receiver Jerome Simpson's post-suspension return. The team used a one-game roster exemption for him this past week after Simpson served a six-game penalty for violations of the league's substance abuse policy.
Bethea was scheduled for an MRI exam on the shoulder at nearby Stanford. He grabbed Seahawks wideout Doug Baldwin with his right shoulder in the second quarter and received a face mask penalty, and that's believed to be when he got hurt.
The 31-year-old Bethea, in his second season with the Niners and 10th in the NFL, had started all 23 games since joining the 49ers as a free agent in March last year. He made 44 tackles and a sack this year.