Rams will exploit 49ers' biggest defensive weakness on Thursday night

The 49ers' injury report for Week 15 isn't great, and one figures the Rams will point out arguably the biggest defensive issue on Thursday night.

Short weeks present challenges no matter what the circumstance, but Thursday night games offer more difficulty to teams facing the injury bug.

And that's precisely what the San Francisco 49ers are dealing with as they prepare for a Week 15 Thursday Night Football bout against their NFC West rivals, the Los Angeles Rams.

If there's a lone positive, the Niners may welcome back star linebacker Dre Greenlaw, who'd be making his 2024 debut after suffering a torn Achilles in the Super Bowl last February.

However, one of San Francisco's biggest weaknesses this season might have to take the field because of injuries elsewhere.

Rookie safety Malik Mustapha, who has been something of a sensation for the 49ers this season, has been ruled out of Thursday night's game because of a chest injury, which means the Niners have to turn to second-year pro Ji'Ayir Brown in the former's stead.

Brown, who was effectively benched in Week 14's win over the Chicago Bears upon the return of All-Pro safety Talanoa Hufanga, has had a downward-trajectory season of his own, struggling in coverage and even allowing one of Chicago's two touchdowns in that particular tilt.

LA is going to take full advantage of this in prime time.

Rams will attack Ji'Ayir Brown at will on Thursday night

Los Angeles has averaged 28.25 points per game over its last four bouts, going 3-1 during that span and coming off a massive back-and-forth victory over the Super Bowl-contending Buffalo Bills a week ago.

Head coach Sean McVay figures to give his quarterback, Matthew Stafford, plenty of options to exploit Brown's weakish coverage skills by using his top two wide receivers, Cooper Kupp and Puka Nacua, throughout Sunday night.

Related story: How to watch 49ers vs. Rams on Thursday Night Football (with and without cable)

Perhaps the biggest hope San Francisco can respond with is up front with a pass rush that'll bank on defensive end Nick Bosa, questionable for the affair, being close to 100 percent after missing the previous three weeks with hip and oblique injuries.

Likewise, the 49ers do know their cornerback trio of Charvarius Ward, Deommodore Lenoir and Renardo Green are about as healthy as can be for Thursday night.

Still, Brown might be the Niners' weakest link against a potent Rams offense, and that could be the biggest X-factor when the two NFC West foes face off on Dec. 12 at 8:15 p.m. from Levi's Stadium.

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