Nick Bosa’s Tendinitis Puts the 49ers’ Pass Rush on Hold for 2026

Defensive end Nick Bosa is dealing with right-knee tendinitis following his recent ACL reconstruction. While the coach emphasized there is no immediate concern for the season opener in September, the uncertainty surrounding his availability persists throughout the 2026 campaign.

Nick Bosa’s Availability for San Francisco 49ers Could Be in Limbo ALL Season Following Worrisome Report

Bosa’s knee issues date back to his high-school years at St. Thomas Aquinas in Fort Lauderdale, where he suffered his first ACL tear. He underwent a second ACL repair on the same knee in 2015, then tore the ACL and meniscus in his left knee in 2020. Most recently, an ACL tear in September 2025 forced him to miss all but three games that season. The current tendinitis is linked to the cumulative trauma of those surgeries.

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• Contract: Bosa signed a five-year, $170 million extension in 2023. The deal carries a $22.9 million cap hit for 2026 and escalates to $54.9 million in 2027.

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• Injury History: Two season-ending ACL tears in his right knee, a third knee surgery, and a prior left-knee ACL/meniscus injury.

Nick Bosa’s Availability for San Francisco 49ers Could Be in Limbo ALL Season Following Worrisome Report

• Performance: In 2021 and 2022, Bosa recorded 34.0 sacks and 40 tackles for loss, leading the league in both categories in consecutive seasons.

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Coach Shanahan described the tendinitis as “a normal thing” for players returning from ACL reconstruction and stressed the need for “smart, week-to-week” management. He noted that Bosa was “doing great” in individual drills before developing soreness, and that the team will evaluate his condition continuously rather than place him on the physically unable-to-perform list. Shanahan also indicated that most starters, including Bosa, are unlikely to appear in the preseason opener against the Titans.

New York Times

Bosa’s health is central to the 49ers’ defensive identity. The edge-rusher is expected to mentor younger players such as Mykel Williams and Romello Height while anchoring a pass rush that produced a league-low 20 sacks last season. Analysts highlight that a healthy Bosa could be pivotal for the team’s Super Bowl aspirations, especially given the concurrent return of linebacker Fred Warner and tight end George Kittle from injury. Conversely, prolonged absences could force the 49ers to rely on veteran additions and could strain the defense’s ability to pressure opposing quarterbacks.

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• “He was doing great, and then he got sore just going through some of the individual (drills),” — Kyle Shanahan, head coach

New York Times

• “The tendinitis that Bosa is dealing with actually stems from the first ACL injury he sustained in high school on this knee (right),” — Bleacher Report’s James Palmer

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• “Bosa is coming off his third knee surgery — and the second ACL injury to the same knee — and is being asked to carry the 49ers’ pass rush while mentoring young players Mykel Williams and Romello Height,” — The Athletic’s Vic Tafur

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• “San Francisco really needs a healthy season — something it seemingly has never experienced in franchise history,” — R’s Brad Gagnon (on July 1)

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