49ers' Christian McCaffrey suffered potential season-ending injury in Bills loss

San Francisco 49ers running back Christian McCaffrey suffered a knee injury that caused his night to end early in Sunday's loss against the Buffalo Bills. Now, they're pessimistic about his chances of playing again in 2024.

49ers coach Kyle Shanahan told reporters that McCaffrey suffered a PCL injury that could sideline him for the rest of the season following their 35-10 loss to the Bills that dropped them to 5-7 on the season. 

In the second quarter, McCaffrey stepped awkwardly on a sweep to the left on a snow-slicked field. The All-Pro went down almost immediately for a 5-yard loss. He went to the sideline and was examined in the medical tent.

McCaffrey was initially ruled as questionable to return, but Shanahan told the NBC broadcast that the running back would miss the remainder of the game after halftime. 

The outing was McCaffrey's fourth this season after the 2023 offensive player of the year missed the Niners' first eight games with Achilles tendinitis. His 19-yard run in the first quarter was his longest of the season, and he had seven carries for 53 yards and two catches for 14 yards before getting hurt.

In four games, McCaffrey has totaled 50 carries for 202 yards, along with 15 catches for 146 yards. He has not scored a touchdown this season.

Jordan Mason took over as the 49ers' featured back when McCaffrey left and finished with 13 carries for 78 yards. Isaac Guerendo also ran the ball four times for 19 yards and a touchdown.

The Associated Press contributed to this report.

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