The bad news keeps coming for the San Francisco 49ers. After a win over the Chicago Bears last week, the vibe was on an upward trajectory. But it only took two days for it to come crashing back down.

Earlier this week, wide receiver Deebo Samuel took to social media to express his dissatisfaction with his role in the offense. The post drew unnecessary media attention, including a response from Super Bowl champion Mark Schlereth.

Today, San Francisco has learned two key starters will not play in Thursday Night’s playoff-implicating matchup vs. the Los Angeles Rams.

49ers Playing Without Two Key Starters

The San Francisco 49ers have ruled out left tackle Trent Williams and safety Malik Mustapha against the Rams.

Williams, still nursing an ankle and heel injury, has not played since the team’s Week 11 loss vs. the Seattle Seahawks on November 17th. Thursday will be San Francisco’s fourth consecutive without their All-Pro left tackle.

This season, the 49ers are 1-2 without Williams blocking quarterback Brock Purdy’s blindside. Since 2020, they are 4-8 when Williams does not play, with two wins over the Rams during that stretch.

Mustapha, who suffered a chest and shoulder injury in last week’s win over the Chicago Bears, is on track to miss the first game of his rookie season.

San Francisco was hopeful Mustapha could this play week after participating in the team’s walkthrough Tuesday night. But the injury has proven too severe to play through. There has been no indication Mustapha is expected to miss multiple weeks.

With Williams and Mustapha ruled out, the 49ers will turn to familiar faces to start in their place.

Replacing Williams and Mustapha

Former fifth-round pick Jaylon Moore will start in Williams’ absence. Moore has started the last three games putting up a rather solid performance.

Since Week 12, Moore has a 77.6 offensive grade and has done his job keeping Brock Purdy upright. In 86 pass-blocking opportunities, Moore has allowed zero sacks, four pressures, and a 97.6 efficiency rating, according to Pro Football Focus.

To put Moore’s performance in perspective, his pass-blocking efficiency rating in the last three games is 0.1 points higher than Trent Williams’ this season.

Replacing Mustapha will be former third-round pick, Ji’Ayir Brown. Brown has started all but one game for San Francisco this season. 

After struggling, Brown was benched for the returning Talanoa Hufanga last week. In 13 games this season, Brown has totaled 63 tackles and one interception but has never found consistency in coverage or as a run defender.

In 2024, he has a 68 coverage grade, which has dipped below 50 four times times season. Brown’s run defense grade is even worse, sitting at a 51.3 season average. Meanwhile, Mustapha has a 77.2 run grade, per Pro Football Focus. — the best on the team.

Moore and Brown will have their hands full on Thursday. 

The Rams’ defense has the 10th-highest pass-rushing grade and 13th-highest pressure percentage, per Pro Football Reference. 

Los Angeles’ offense is also coming off a 44-point performance against the Buffalo Bills, where quarterback Matthew Stafford passed for 320 yards and two touchdowns. Against Buffalo, the Rams also rushed for 137 yards and three touchdowns.

Rams list 3 players as questionable for TNF vs. 49ers

The Los Angeles Rams unleashed an offensive onslaught in their Week 14 matchup against the Buffalo Bills. Despite a ridiculous, record-breaking six-touchdown game from Josh Allen and a 21-point fourth quarter, the Rams got the 44-42 win in a wild shootout.

LA’s offense is heating up in time for a playoff push as the 7-6 Rams are just a game behind the first-place Seattle Seahawks in the NFC West. However, Los Angeles could be down a trio of pass catchers for a hugely important divisional clash with the San Francisco 49ers on Thursday night.

Wideouts Demarcus Robinson and Jordan Whittington and tight end Davis Allen are all listed as questionable for LA’s Week 15 matchup, according to NFL insider Adam Schefter on X. All three players are dealing with shoulder injuries.

Robinson is the most impactful player of the group. The ninth-year veteran is fourth on the team in receiving yards and he leads the Rams with seven receiving touchdowns. The former Chiefs wideout is having a career year in 2024 with 28 receptions for 433 yards and seven scores. And he had a highlight reel, game-winning touchdown catch against the Seahawks in Week 9.

WR Demarcus Robinson leads the list of injured Rams ahead of Week 15’s divisional clash

Whittington is in his rookie season after being drafted in the sixth round by the Rams in 2024. Head coach Sean McVay is excited for Whittington’s potential but the young receiver has yet to establish himself as a mainstay in LA’s offense.

Week 14 was the Puka Nacua show as his historic game helped the Rams beat Buffalo. Nacua caught 12 passes for 162 yards and a touchdown while adding five carries for 16 yards and another score.

Since returning in Week 8 from a five-game absence due to injury, the second-year WR has been on a tear. He’s up to 54 receptions with 743 total yards and four touchdowns in eight games.