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49ers' Fred Warner opens up about Nick Bosa's injury

Originally posted on 49ers Webzone | By David Bonilla | Last updated Sep 24, 2025 5:57 PM ET

The San Francisco 49ers are now facing the season without one of their defensive anchors, defensive end Nick Bosa. Bosa suffered a season-ending ACL tear in Sunday's victory over the Arizona Cardinals, leaving a significant void along the defensive front.

Star linebacker Fred Warner, another leader on the 49ers defense, spoke to reporters Wednesday about the impact of Bosa's injury.

"I'm sick," Warner said. "I'm so sick for him because he knows what that's like, to go through that process of a recovery from that injury, which I know he's fully capable of. But that doesn't make it any easier."

This marks the second ACL injury Bosa has suffered since entering the NFL and the third overall since high school. He previously tore his left ACL in 2020. This time, it's his right ACL—the same one he partially tore in high school.

"Obviously, it's a huge blow to our team, but we move forward," Warner continued. "I hate to say 'next-man-up mentality' because you can't just replace him with one player, but the mission is still the same. We're going to find a way just to get one win this week, and we'll figure out the rest later."

Fred Warner reemphasizes the fact that Nick Bosa isn't a guy that you can replace with one player. He said he sat and spoke with him right when he found out about the injury. #FTTB | #49ers pic.twitter.com/RsDjp9ADxc— Matt Lively (@mattblively) September 24, 2025

Warner also shared that he's had a chance to speak with Bosa directly since the defensive end officially learned he would miss the rest of the season.

"I sat and talked with him right when he found out, and we spoke about it," Warner shared. "And obviously, he's devastated and we're devastated for him, but we're just praying for him, and obviously, whenever he gets the surgery, that it goes great and everything with his recovery."

Head coach Kyle Shanahan addressed concerns about this being Bosa's second right ACL injury and third ACL tear overall.

"I think there's zero worry or correlation between the three," Shanahan said. "I mean, this one, from what they say, is as clean as anyone you can do. I mean, just pure ACL and nothing else. The other ones, they've all been five years apart.

"I had a buddy who tore one in high school, tore two in college, and then played eight years in the NFL without one. I think Frank Gore's done it a number of times. So, it's all about how it heals and what type of tear it is. When it's clean and you go through the rehab and stuff, it's usually brand new after that."

The 49ers now must adjust without their star pass rusher, relying on depth and leadership from players like Warner to keep the defense competitive down the stretch.

This article first appeared on 49ers Webzone and was syndicated with permission.

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