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49ers Sign Defensive End After Losing Nick Bosa To Season-Ending Injury

Originally posted on The Spun | By Andrew Gould | Last updated Sep 23, 2025 5:26 PM ET

The San Francisco 49ers will look to turn the page without Nick Bosa.

Head coach Kyle Shanahan confirmed Monday that Bosa suffered a torn ACL in Sunday's 16-15 win over the Arizona Cardinals. The superstar pass rusher will undergo season-ending surgery.

No free agent will come close to matching Bosa's impact, but the 49ers made a minor move to add depth to the defensive line. According to NFL Network's Mike Garafolo, San Francisco signed William Bradley-King to the practice squad.

More on Bradley-King

Bradley-King spent two weeks with the 49ers in August. They released him when signing defensive lineman Evan Anderson and offensive lineman Kilian Zierer to the practice squad on Aug. 29.

The Washington Commanders made Bradley-King the No. 240 pick of the 2021 NFL Draft. The Baylor alum played four games over two seasons, notching seven tackles and 0.5 sacks on 84 career snaps.

Bradley-King hasn't played in an NFL game since Week 3 of the 2022 season. He's since spent time with the New England Patriots and Miami Dolphins without getting called off the practice squad.

San Francisco gives the 6-foot-4, 265-pounder another opportunity to earn NFL reps.

Life without Bosa for San Francisco

Sep 21, 2025; Santa Clara, California, USA; San Francisco 49ers defensive end Nick Bosa (97) on the field during warm ups prior to a game against the Arizona Cardinals during the first half at Levi's Stadium. Mandatory Credit: Cary Edmondson-Imagn Images

San Francisco's defense takes a significant hit without Bosa, who recorded four pressures and two sacks before his season-ending surgery. The 49ers lost two of three games without the 2022 Defensive Player of the Year last season, allowing 73 combined points in road shortcomings to the Buffalo Bills and Green Bay Packers.

The 49ers have allowed the NFL's third-fewest yards and fourth-fewest points amid a 3-0 start. Their other defenders have also mustered just three sacks, so they may struggle to pressure the quarterback without Bosa.

"You don't just replace a guy like Nick," Shanahan said. "Everyone has to get better."

It's another blow to a 49ers squad also dealing with injuries to Brock Purdy, Brandon Aiyuk, and George Kittle. San Francisco will host the Jacksonville Jaguars this Sunday.

This article first appeared on The Spun and was syndicated with permission.

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