The San Francisco 49ers cannot catch a break. Defensive End Nick Bosa, who just returned this season from a torn ACL is now expected to miss multiple weeks with a calf injury. According to 95.7 The Game in San Francisco and 49ers insider Jennifer Lee Chan, Bosa has a “serious injury,” and, “if he’s not out for the season, he’s out for multiple weeks.”

Adam Schefter then confirmed the worst fears: Nick Bosa pulled his calf in yesterday’s practice and is expected to miss multiple weeks now. The 49ers are now trying to figure out whether to put him on injured reserve or not. Thus adding to a long list of injuries on San Francisco’s defensive front. 

Bosa’s return was already a bright spot

Look, Bosa had been a welcomed return for the 49ers. He clearly made a difference in Week 1 up front for San Francisco against the Los Angeles Rams. The fact that he worked his way back from an ACL tear and was ready for the season opener was one of the best storylines surrounding this team. Now he’s dealing with knee and calf injuries and it seems like this all could be for not.

What is going on with Nick Bosa? Obviously, an ACL injury is serious. That takes a lot of time to recover from, and missing almost the entire 2025 season before coming back for Week 1 this year was already a long road. But injured again? This is getting ridiculous at this point.

For reference, Nick Bosa tore his ACL in Week 3 of 2025 against the Arizona Cardinals and was just able to make it back roughly 50 weeks later. It’s been a long road for this guy over the past year. 

The 49ers’ injury nightmare continues

You can’t necessarily point the finger at Bosa himself, but the situation is not looking good. This team and some of these players have to figure out how to take care of their bodies. Bosa is a player the 49ers desperately need.

In the last two weeks the 49ers have lost the following: Nick Bosa (calf), Alfred Collins (torn patellar tendon), Sam Okuayinonu (broken foot), James Thompson Jr. (high ankle sprain), Romello Height (broken hand) and CJ West (bone chip in knee). 

That front is brutally banged-up. And that’s the cruel irony with this San Francisco team. It seems like every time something good happens, something bad has to follow. The 49ers got good news this week that Mykel Williams is about to return soon. Well, there’s got to be a catch, right? And there is. Nick Bosa is going to miss some time for the 49ers.

Bosa’s long injury history

Nick Bosa, unfortunately, is a guy who is not new to missing some time. Bosa tore his ACL in Week 2 of the 2020 season which caused him to miss the rest of the year. Then, Bosa suffered a groin strain in 2022, an oblique strain in 2024 and the ACL tear last year in 2025. Obviously, Bosa plays a high-contact position on the defensive line and stuff happens. 

But for a player of his magnitude, he needs to be on the field more and stay healthier in general. He is currently 28 years old and signed a five-year, $170 million extension with the team in 2023. You almost have to wonder what his future with the team looks like at this point. 

What this means for San Francisco’s defense

I think San Francisco is in a tough spot here. Nick Bosa is the kind of player who changes the entire complexion of the 49ers defensive line. Losing him again after what was supposed to be a triumphant comeback puts this defense in a precarious position. San Francisco was already thin up front before this news, and now they’re looking at potentially placing their best pass rusher on injured reserve.

Whether this turns into an IR stint or just a few missed weeks, this is a major blow for a team that was counting on Bosa to anchor their pass rush all season long. Again, it will be good for them to get Mykel Williams back in the coming weeks, no doubt about that. 

But the point remains: when something good happens with this team, something bad follows.