49ers slammed with even more brutal injury news after loss to Bills

Things keep going from bad to worse for the injury-depleted 49ers, who'll be down even more running backs after losing to the Bills.

It seems as if the San Francisco 49ers hit a new low each and every week, and their ugly 35-10 defeat at the hands of the Buffalo Bills in Week 13 was a new benchmark.

Particularly on the injury front with All-Pro running back Christian McCaffrey initially appearing as if he was getting back to his Offensive Player of the Year ways early in the Sunday Night Football contest before exiting the game with what turned out to be a PCL injury.

McCaffrey didn't return to the game, and the initial postgame fear was that he suffered a potentially season-ending knee injury.

But wait. There's more on the Niners' injury front. And it's not good.

49ers tack on Jordan Mason to injured reserve list

San Francisco managed to get by over the first eight weeks of the season, thanks largely to backup running back Jordan Mason emerging as a bell cow in McCaffrey's absence. At one point, Mason was the league's No. 2 rusher behind only Derrick Henry of the Baltimore Ravens, and the former made it through Week 13 with 789 rush yards, three touchdowns and an impressive 5.2 yards per carry.

Unfortunately, as head coach Kyle Shanahan pointed out during his Monday press conference, Mason suffered a high-ankle sprain at Buffalo and will land on injured reserve.

Mason saw a dramatic decline in use upon McCaffrey's return from IR in Week 10 and figured to be the primary beneficiary of any return to the injured list by McCaffrey.

However, with Mason's own setback, the primary duties of running the ball now all but go to rookie rusher Isaac Guerendo, who is averaging 5.9 yards per carry on the season.

The 49ers will have to engineer a transaction or two to bolster what's now a completely injury-decimated running back room in the wake of both McCaffrey and Mason heading to IR.

Additionally, Shanahan told reporters defensive tackle Kevin Givens suffered a torn pectoral and will go on injured reserve, ending his season.

Brutal.

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