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The San Francisco 49ers will be without star defensive end Nick Bosa for the rest of the 2025 season after he tore his ACL during Sunday’s win over the Arizona Cardinals.
Bosa’s tear was a clean one and will require season-ending surgery, according to ESPN. He is expected to begin a long recovery in hopes of returning by the start of the 2026 campaign.
Unfortunately for Bosa, he is no stranger to this injury. He also tore his ACL in Week 2 of the 2020 season against the New York Jets and partially tore the ligament in high school in 2015.
The injury occurred late in the first quarter of San Francisco’s 16-15 victory over its NFC West rival. Bosa walked to the locker room with about a minute remaining in the period and did not return. Head coach Kyle Shanahan said initial sideline tests did not indicate an ACL tear, though he cautioned a serious injury was possible.

San Francisco 49ers defensive end Nick Bosa (97) leaves the field at Caesars Superdome on Sept. 14, 2025. (Matthew Hinton/Imagn Images)
“There is concern because of how he feels,” Shanahan said Sunday night. “They do the test and stuff on the sideline, and usually they say whether he definitely did or not [injure his knee], and they didn’t say that. But we are concerned with that. Keeping our fingers crossed for the MRI.”
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Bosa was rushing Cardinals quarterback Kyler Murray from the left side when he engaged with left tackle Kelvin Beachum. Guard Evan Brown came over to help, and Bosa was knocked to the ground. His knee buckled awkwardly before he hit the turf, and he walked slowly to the sideline with trainers before heading to the locker room.
San Francisco 49ers defensive end Nick Bosa (97) on the field during warmups prior to a game against the Arizona Cardinals during the first half at Levi’s Stadium on Sept. 21, 2025. (Cary Edmondson/Imagn Images)
The seven-year veteran had started the season strong, recording two sacks, four tackles for loss and two forced fumbles in three games.
“Anytime you lose a guy like Nick and his status is unknown, it’s a real buzzkill,” All-Pro left tackle Trent Williams told ESPN. “It is cliché to say the next man up, but when you lose a guy like that, you need three or four guys to come fill those shoes.”
San Francisco will now turn to its depth, with rookie Mykel Williams, Bryce Huff, Yetur Gross-Matos and Sam Okuayinonu expected to step up in Bosa’s absence.
Nick Bosa of the San Francisco 49ers stands on the sidelines during the national anthem prior to an NFL football game against the Arizona Cardinals at Levi’s Stadium on Sept. 21, 2025 in Santa Clara, California. (Brooke Sutton/Getty Images)
The 49ers’ injury woes just continue to pile up, as stars on the offensive side – tight end George Kittle and quarterback Brock Purdy – are also out with their own respective ailments. However, they are not expected to be season-ending like Bosa.
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https://www.foxnews.com/sports/49ers-lose-star-nick-bosa-remainder-2025-season-torn-acl-reports