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.
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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.