49ers loss could be Seahawks' gain in NFC West

Nick Bosa won't beat the Seattle Seahawks again. At least not in the 2025 season.

Bosa, the San Francisco 49ers' perennial Pro Bowl edge-rusher, suffered a torn ACL in his right knee Sunday and is lost for the season. He played a major role in handing the Seattle Seahawks their only loss of the season, when he forced and recovered quarterback Sam Darnold's fumble inside the Niners' 10-yard line in the final minute of Week 1.

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Seahawks players - and the 12s - would never cheer for an opponent's injury, but ... there's no way around this being positive news for their quest to win the NFC West. The rival 49ers have already played games this season without quarterback Brock Purdy, tight end George Kittle and receivers Jauan Jennings and Brandon Aiyuk. Now they'll be without Bosa for the final 14 games.

Tests today showed that 49ers Pro Bowl DE Nick Bosa suffered a season-ending torn ACL during Sunday’s win over Arizona, sources tell ESPN. It’s a clean tear, but Bosa now will need season-ending surgery. pic.twitter.com/f6xdHY0iVS
— Adam Schefter (@AdamSchefter) September 22, 2025

While Seattle was throttling the New Orleans Saints, the Niners were beating the Arizona Cardinals on a last-second field goal to improve to 3-0. Bosa suffered his injury late in the first quarter and didn't return. He had two sacks, eight pressures and 15 tacklesw in the first two games, including the game-saving play against Darnold in San Francisco's 17-13 win at Lumen Field.

The Seahawks travel to Levi's Stadium in Santa Clara for a rematch with the Niners in Week 18 in early January.

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Without Bosa, the Niners will count on pass-rush pressure from the likes of rookie Mykel Williams and veteran Bryce Huff.

"Anytime you lose a guy like Nick and his status is unknown, it's a real buzz kill," Niners' veteran offensive lineman Trent Williams said Sunday. "It is cliche to say the next man up, but when you lose a guy like that, you need three or four guys to come to fill those shoes."

The 49ers celebrate after a fumble recovery during the second half against the Seahawks | Joe Nicholson-Imagn Images

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