The San Francisco 49ers will be without one of their defensive leaders for the remainder of the season. Head coach Kyle Shanahan announced that linebacker Fred Warner will miss the rest of the year after suffering a dislocated and fractured ankle in Sunday's loss to the Tampa Bay Buccaneers. Warner underwent successful surgery on Tuesday and is expected to make a full recovery in time for offseason workouts in the 2026 season.
With Warner sidelined, second-year linebacker Tatum Bethune will take over the team's MIKE linebacker duties against the Atlanta Falcons on "Sunday Night Football."
"Tatum, to me, is so made of the right stuff. He's so handled this year and a half the right way that he's definitely more than ready for this opportunity," Shanahan said on Wednesday.
Bethune entered last week's game following Warner's injury and quickly took command of the defense. He logged 23 snaps against the run, two as a pass rusher, and 20 in coverage versus quarterback Baker Mayfield and the Buccaneers offense. Bethune finished with a career-high 10 tackles, leading the defense in total stops in Week 6. Shanahan acknowledged a few miscues; however, Bethune's overall performance was a bright spot on film.
"There's lots of stuff I can show our guys and stuff from the tape that's very encouraging of some real good things Tatum did when he went in and replaced him (Warner)," Shanahan said Monday. "Tatum had a lot on his plate. He came in and I thought he did a lot of good things getting us lined up, but I think that's something he'll be a lot more ready for next week getting all the reps."
While reviewing the full game film, Shanahan admitted it was "a little depressing" to re-watch the series of events that led to Warner's injury. The head coach stopped himself to see the tape in a different perspective, and his confidence in the younger players stepping up, including Bethune, had only grown.
"It was very inspiring watching how Tatum played. A bunch of our young guys, there are some good things on that tape. Got to clean up some mistakes that we made, but I liked how the film looked and how the guys played."
Bethune, who was a seventh-round draft pick, will now assume the green dot responsibilities on defense, meaning he'll be the one communicating play calls from the sideline to his teammates on the field.
While stepping in for Warner is no small task, Shanahan believes Bethune's preparation and athleticism make him ready for the role.
"It has to start with how you play linebacker. Can you run? Can you hit? Can you make tackles? Can you cover people? I thought he did that at a very high level in college, and he's done it very well since he's gotten here. This is why he made our team," Shanahan said. "We've liked him since the beginning. He's shown that ability. I think it's been good for him to be behind someone like Fred and see how he does it."
Cornerback Deommodore Lenoir echoed Shanahan's confidence in Bethune, sharing that Warner had been intentional about helping Bethune develop as a leader.
"It's kinda crazy because Fred used to always make Tatum break down the team, so I've seen the leadership in him already," Lenoir said. "Just hearing him talk, I know he's made of the right stuff. I've got the upmost confidence in him. I feel like he's gonna do great out there."
Bethune's opportunity to start at MIKE linebacker is a pivotal moment for both the sophomore player and the 49ers defense as he steps into one of the team's most demanding roles.
