Luter (pelvis) was placed on the 49ers' injured reserve Saturday, Matt Barrows of The Athletic reports.
Luter appears to have injured his pelvis during practice this week, as he popped up on Friday's injury report as a DNP. It's serious enough to warrant a multi-game absence, and since he'll be forced to miss at least the next four regular-season games, the earliest Luter can return would be Week 15 against the Rams on Thursday, Dec. 12. Luter has played in just three games and has mostly played on special teams.