The San Francisco 49ers injury list continues to grow in the second half of the season. Following their Week 13 loss to the Buffalo Bills, head coach Kyle Shanahan delivered unfortunate injury updates on his top two running backs and an important role player on the defensive line.

Reigning AP NFL Offensive Player of the Year Christian McCaffrey suffered a PCL injury in the second quarter of Sunday night’s contest. Shanahan shared that while initial reports suggest he will not need surgery, McCaffrey’s recovery timeline is estimated to be about six weeks, and he will be placed on the Injured Reserve list.

“I feel for him. It was a really frustrating year for him,” Shanahan said. “…I think he was really feeling good and about to take off. He just had that really unfortunate injury last night. I know he is as crushed as anyone, but he will get through this.

“He is a hell of a player, hell of a person and an unbelievable 49ers player. He’ll be back stronger than ever next year to help us.”

McCaffrey spent the first nine weeks of the season on IR on account of Achilles tendonitis before returning to start the last four games. He recorded 50 carries for 202 yards on the ground and added 15 catches for 146 yards receiving in those contests.

Fellow running back Jordan Mason is also headed to IR after sustaining a high ankle sprain against the Bills. Mason was the 49ers primary running back through the first eight weeks of the season, filling in for an injured McCaffrey. The former undrafted free agent rose to the occasion this season and put together an impressive stat line. Mason logged 153 carries for 789 yards and three touchdowns to go with 11 catches for 91 receiving yards in his 12 appearances (six starts).

With San Francisco’s top two running backs out of the lineup, rookie Isaac Guerendo is now the team’s top option at running back. Shanahan said he expects to elevate Patrick Taylor Jr. from the practice squad and will look to add another to the 53-man roster to round out the room.

The third player expected to land on IR is defensive lineman Kevin Givens after tearing his pectoral muscle on Sunday night. Givens was coming back from a lingering groin injury and served as an important depth player for the 49ers D-line in 2024. He appeared in eight games (one start) this season and amassed 3.5 sacks and 11 total tackles in those outings.

Outstanding injuries: