San Francisco 49ers defensive end Nick Bosa (97) during training at the Levi's Stadium practice field in Santa Clara on Wednesday, June 11, 2025. (Santiago Mejia/S.F. Chronicle)
Nick Bosa suffered a strained calf this week and the San Francisco 49ers' All-Pro pass rusher is expected to be sidelined for multiple weeks, ESPN reported Friday.
The 49ers are determining whether to place Bosa on injured reserve, which would require him to miss a minimum of four games. If placed on IR, Bosa would be eligible to return when the 49ers visit the Falcons on Oct. 25.
Bosa's injury is the latest to befall what was already a threadbare defensive line entering a Week 3 meeting against the Cardinals on Sunday at Levi's Stadium. And it's also the most significant. The 49ers had a NFL-worst 20 sacks in 2025, a season during which Bosa, 28, a five-time Pro Bowl selection, suffered a torn ACL in Week 3 against Arizona.
On Thursday, defensive tackle Osa Odighizuwa termed the attrition up front a "horror show." In the past three weeks, the 49ers have lost Sam Okuayinonu (broken foot), Alfred Collins (torn patellar tendon), CJ West (chipped knee bone) and James Thompson (high ankle sprain) to significant injuries.