49ers' Mykel Williams: Diagnosed with torn ACL

Head coach Kyle Shanahan said Monday that Williams tore his ACL during the fourth quarter of Sunday's 34-24 win over the Giants, Matt Barrows and Dianna Russini of The Athletic report.

Shanahan noted that there was some damage to the lateral meniscus in Williams' knee but no other ligament damage beyond the ACL, which means the rookie first-rounder has a chance to be available for the start of the 2026 campaign. It's yet another season-ending injury for the 49ers defense, with Williams stepping into a larger role on the defensive line after Nick Bosa tore his ACL in Week 3 against the Cardinals and All-Pro linebacker Fred Warner lost for the season after dislocating and fracturing his right ankle in Week 6 against the Buccaneers. Fellow defensive end Yetur Gross-Matos will miss at least three more games while on injured reserve due to a hamstring injury, but veteran Bryce Huff (hamstring) is expected to return from a two-game absence against the Rams in Week 10. In the absence of Bosa, Gross-Matos and now Williams, the 49ers will rely more heavily on the likes of Huff, Sam Okuayinonu, Clelin Ferrell and Keion White (who was traded by New England to San Francisco this past Tuesday) at defensive end. Barrows and Russini also note that the 49ers are looking to add to the position before Tuesday's 4 p.m. ET deadline and have shown interest in Jaelan Phillips (who the Eagles acquired from the Dolphins on Monday), Bradley Chubb and Matthew Judon.