The San Francisco 49ers received some terrible news on Monday morning, as tests revealed that Nick Bosa suffered a season-ending torn ACL. ESPN’s Adam Schefter said it was a clean tear. However, Bosa will still need season-ending surgery.
This is the second time Bosa has torn his ACL as a pro. He tore his ACL as a senior in high school. It’s the same knee he tore in Week 2 of 2020 against the New York Jets. Here’s the final play of the game for Bosa:
This was Nick Bosa’s final play of the game. He’s rushing off to the left side of the screen. It looks like his right knee gives out on the final step where he plants, and that’s what really takes him to the ground. Worst-case scenario for the 49ers. pic.twitter.com/0KGEwntWOL
— Kyle Posey (@KP_Show) September 22, 2025
You have to feel for any player suffering an injury. That’s especially the case when it’s the team’s best and most impactful player. Bosa has been dominant to date. He’s among the league leaders in several categories, despite missing much of Week 3.
The 49ers will ask even more from their young defensive line. Mykel Williams will likely see an uptick in snaps. San Francisco had found ways to keep their deep defensive line group rested during games. For example, Bosa would sit out multiple series in the second quarter. They will no longer have that luxury.
Through three games, Robert Saleh has been reluctant to use Bryce Huff and Yetur Gross-Matos on running downs. We can probably expect Sam Okuayinnonu to start in Bosa’s place, with Gross-Matos and Huff continuing to play on obvious passing downs. As well as Sam O has played, he’s a role player. The drop-off is undescribable from Bosa to anybody, let alone Okuayinonu.
Saleh will be forced to get even more creative than he’s been without Bosa. That likely means more Mykel and bigger bodies on early downs. It’s worked so far, as the 49ers have the second-highest stuff rate in the league through three games.