The San Francisco 49ers have suffered a significant blow as defensive end Nick Bosa has been ruled out for the remainder of the season due to a torn ACL in his right knee. This unfortunate news was confirmed by league sources on Monday, following the results of an MRI conducted after Bosa's injury during the game against the Arizona Cardinals.
The MRI revealed a complete tear of Bosa's ACL, but fortunately, no other ligaments were damaged. This is promising news as it suggests that he will undergo a clean surgical procedure and potentially face a smoother recovery process. This marks the third severe knee injury in Bosa's football career, raising concerns for the future of this talented player.
In 2020, during his second season in the NFL, Bosa suffered a similar fate when he tore both the ACL and meniscus in his left knee, which prematurely ended his season just two games in. Additionally, while in high school at St. Thomas Aquinas in Fort Lauderdale, Florida, Bosa underwent surgery for a partially torn ACL in his right knee back in 2015.
Bosa's injury occurred late in the first quarter of the game against the Cardinals. After being flattened by a double team, he limped to the sideline, where he received medical attention. A thumbs-down gesture indicated his disappointment as he made his way to the medical tent. Initially, he was deemed questionable to return, but by halftime, it was clear he would not be returning to the field.
As of now, Bosa has concluded the 2025 season with impressive stats, including two sacks, two forced fumbles—one of which was crucial in securing the Week 1 victory against the Seattle Seahawks—and 17 tackles, with four tackles for loss and three quarterback hits. Over his career, he has amassed 64.5 sacks, been selected for five Pro Bowls, and earned one first-team All-Pro honor.
Following the game, defensive end Bryce Huff expressed his sorrow over Bosa's injury, acknowledging the pivotal role he plays on the defensive line. "He’s been such a pillar of our defensive line, doing everything he can to help us get better and lead the way," Huff stated. "It hurts me to see him hurting like that."
With Bosa sidelined, the 49ers will need to adapt quickly. Players like Huff, who recorded a sack during the game, and rookie Mykel Williams have stepped up in Bosa's absence. Additionally, sixth-year veteran Yetur Gross-Matos is expected to take on a larger role despite being limited by a knee injury that has restricted his practice time since training camp.
The 49ers have faced challenges this season, already missing key players such as quarterback Brock Purdy, tight end George Kittle, and wide receivers Brandon Aiyuk and Jauan Jennings. However, they remain undefeated at 3-0, heading into a crucial Week 4 home game against the Jacksonville Jaguars.
Despite the setback, there is reason for optimism regarding Bosa's recovery. Historically, he has shown remarkable resilience following knee injuries. After his high school surgery, he achieved freshman All-American status at Ohio State, recording five sacks and seven tackles for loss. Following his 2020 ACL tear, Bosa bounced back impressively, notching 15.5 sacks and a career-high 21 tackles for loss in 2021, while starting all 17 games.
The surgery for his previous injuries was performed by renowned orthopedist Neal ElAttrache, who has handled many of the 49ers' ACL injuries, including those of linebacker Curtis Robinson and Aiyuk last season. Bosa's commitment and dedication to his recovery will be pivotal as he navigates this challenging period.
In response to Bosa's injury, the 49ers have already begun strategizing on how to fill the gap left in their defensive lineup. After Bosa's exit from the game, the team relied heavily on defensive ends Williams, Huff, and Sam Okuayinonu, who led the team with quarterback pressures. The 49ers may also opt to elevate one of their defensive ends from the practice squad, such as Robert Beal Jr. or Trevis Gipson, to strengthen their defensive performance moving forward.
As the 49ers prepare for their next game, the focus will be on adapting their strategies and ensuring the team can maintain its strong start to the season, even in the absence of one of its star players.
