The San Francisco 49ers can't seem to catch a break.

Injuries have plagued San Francisco all season, and the Niners will have to deal with even more adversity on that front as they prepare to face the Los Angeles Rams on Thursday night in Santa Clara, Calif.

Just 10 months removed from a Super Bowl appearance, San Francisco (6-7) finds itself sitting in the basement of the NFC West and needing to essentially run the table against the Rams, Miami Dolphins, Detroit Lions and Arizona Cardinals to have a shot at making the playoffs.

Staying healthy has been a seemingly impossible task for the 49ers, whose struggles have centered around a banged-up backfield.

Star running back Christian McCaffrey is done for the rest of the season after appearing in only four games, and backup Jordan Mason joined him on injured reserve after both went down during a Week 13 loss to the Buffalo Bills.

That forced the 49ers to turn to third-stringer Isaac Guerendo for their meeting with the Chicago Bears on Sunday, and the rookie shined with 78 yards and two touchdowns on 15 carries in what ended up being a 38-13 victory.

Guerendo also hauled in two receptions for 50 yards, but he too caught the injury bug. A foot sprain sidelined him in the fourth quarter, and the 24-year-old did not practice Tuesday and is considered a game-time decision against the Rams.

"We'll see if he can go Thursday," San Francisco coach Kyle Shanahan said. "It's a quick turnaround, so we have to evaluate him hard each day. ... Hopefully Thursday will be enough time for him."

Star defensive end Nick Bosa (hip, oblique), guard Ben Bartch (ankle) and offensive tackle Trent Williams (ankle) also didn't practice Tuesday. Linebacker Dre Greenlaw is dealing with an Achilles issue and was among those who were limited.

Los Angeles coach Sean McVay isn't underestimating the 49ers, regardless of what their injury report says.

"If there's anything that you do know, it's a week-to-week league. Humility's only a week away," McVay said. "They have excellent coaches, excellent personnel, really good schemes. And so, no matter what's really happened in terms of the trajectory of the injuries, they're gonna be ready to go and we're gonna do our best to get our guys ready to roll. ...

"It's gonna be a great challenge and opportunity, and I think the familiarity only gives that much more respect knowing (not only) what they've done, but what they're capable of as well."

The Rams (7-6) are peaking at the right time, most recently edging the Bills 44-42 on Sunday for their sixth win in the past eight games. Matthew Stafford completed 23 of 30 passes for 320 yards and two TDs while leaning heavily on Puka Nacua (12 catches, 162 yards, one touchdown).

Kyren Williams found the end zone twice on the ground and finished with 87 yards on 29 carries.

The second-place Rams hold their destiny in their hands, as they face all three NFC West rivals (plus the New York Jets) in the final month.

Stafford could be getting another weapon back in the mix on Thursday, as tight end Tyler Higbee might make his season debut after recovering from a torn ACL and MCL. Higbee practiced in full on Tuesday.

Six Rams didn't practice on Tuesday, including wide receiver Demarcus Robinson (shoulder) and cornerback Cobie Durant (chest).

--Field Level Media