The San Francisco 49ers are being forced to get used to life without Arik Armstead.

Armstead, the veteran defensive tackle, has missed the last two games with knee and foot injuries.

And head coach Kyle Shanahan confirmed he will also be unavailable on Christmas Day when the Niners host the Baltimore Ravens in a battle of number one seeds, though San Francisco looks likely to get back one starter on the defensive line from injury for the substantial test posed by Lamar Jackson and the Baltimore offense.

49ers injury report

Injury report observations

The 49ers had initially hoped Armstead would only be out a couple of games. Now, it looks like they will have to play it week by week because of a foot issue that is similar to the one that significantly hindered his 2022.

Armstead played only nine games last year because of plantar fasciitis and Shanahan said in his Saturday press conference: "We’re concerned, we do think he has a chance each week but it’s a little more the foot than the knee, something that’s bothered him for a little bit so just hoping the pain will go down."

While Armstead will again be reduced to the role of spectator, the signs are much better for his fellow starting defensive tackle Javon Hargrave, who is listed as questionable after practicing in a limited capacity the last two days. The 49ers only did a walkthrough on Saturday.

Alongside Armstead, Hargrave has reinvigorated the Niners' interior pass rush this season. He has six sacks and is the Pro Football Focus' third-ranked interior defensive lineman by pass rush grade.

Defensive end Clelin Ferrell has experience playing inside in his career and could help in an area where the 49ers are suddenly light on depth. Ferrell does not have an injury designation despite dealing with an ankle injury all week.

On the other side of the ball, right guard Spencer Burford has been cleared to make his return from a knee injury that ruled him out of the last two games. Backup running back Elijah Mitchell has hope of avoiding a third straight game on the sideline, as he is listed as questionable with a lingering knee issue.

Jauan Jennings failed to pass through the concussion protocol, meaning the 49ers will be without an excellent run blocker and a receiver who has consistently come up huge in clutch situations.

Shanahan, though, expressed confidence rookie Ronnie Bell can step up in his absence.

With starting SAM linebacker Oren Burks out once again with knee tendinitis, Demetrius Flannigan-Fowles will likely man that role again when the 49ers are in base personnel.

Chargers give 49ers chance to solve lingering defensive problem

He should be of great interest.