San Francisco 49ers running back Jeff Wilson Jr. had a "flare-up" on his surgically repaired knee during Sunday's loss to the Seahawks, per Matt Maiocco of NBC Sports Bay Area. (Matt Maiocco on Twitter)
Head coach Kyle Shanahan told reporters that it has happened before and that it usually bothers Wilson Jr. for a few days before he can get right. This partially explains why Wilson Jr. was a no-show during Sunday's loss against the Seahawks and it makes him questionable heading into next Sunday's game against the Bengals. Starting running back Elijah Mitchell (head) is also in the concussion protocol, which leaves JaMycal Hasty as the only healthy running back on the roster for now.