For now, the 49ers' plan to fill the large shoes Warner leaves behind is similar to what they have done without Bosa since he tore his ACL in Week 3. The 49ers will look in-house, giving younger, less-experienced players an opportunity to get snaps and try to prove they deserve a longer look at the position.

All-Pro LB Fred Warner went down with a serious injury on Sunday that no one wanted to see, especially Todd Bowles.

The injury-ravaged San Francisco 49ers suffered another blow Sunday when linebacker Fred Warner went down with a season-ending ankle injury, which required the four-time All-Pro to be carted off the field during a loss to the Tampa Bay Buccaneers and will require surgery.

What we learned as Fred Warner injured in 49ers’ tough road loss to Buccaneers “The 49ers believe they have good depth at linebacker. They do not need second-year pro Tatum Bethune to be Fred Warner. They just need him to be a solid player who can hold his own in the middle of Robert Saleh’s defense.”