Bosa (oblique) was estimated as a non-participant at Monday's practice, Nick Wagoner of ESPN.com reports.
Bosa has been sidelined for the 49ers' last three games due to a left oblique injury that he aggravated in Week 11 against the Seahawks. Although he is considered day-to-day heading into Thursday's game against the Rams, Bosa hasn't been able to participate in practice since the injury, and he would be a longshot to play unless he returns to practice Tuesday or Wednesday.