SANTA CLARA — Rookie safety Ji’Ayir Brown wasn't scheduled to practice Wednesday because of a knee injury that 49ers coach Kyle Shanahan labeled a “concern.”
Brown’s injury wasn't immediately known after the 49ers' Monday night loss to the Baltimore Ravens.
"There's concern," Shanahan said. "We're not ruling him out this week, but there's concern. That's why he can't go today."
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Meanwhile, the 49ers' front-line depth could be tested in a crucial Week 17 matchup with the Washington Commanders, as three key members of the offensive line weren't fully cleared to practice.
All-Pro left tackle Trent Williams, who usually takes Wednesdays off anyway, would be able to participate in limited practice, Shanahan said, after he sustained a groin injury during the 49ers’ 33-19 loss to the Ravens. Williams' status for Sunday's game against his old team will not be determined until later in the week.
Backup tackle Jaylon Moore would be the 49ers' first option to replace Williams, but he wasn't available to practice after being placed in the NFL's concussion protocol. His status for Sunday's game also is uncertain.
The 49ers also don't have left guard Aaron Banks available after he aggravated a toe injury that kept him out of two games last month.
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"Not practicing, but he's not ruled out this week," Shanahan said. "Hopefully he'll be limited the next day, which basically I'm saying it's not quite as bad as last time, but last time was pretty bad. We've got to see how it goes in these next couple days."
The 49ers re-signed veteran offensive tackle Matt Pryor on Wednesday. He had been waived Monday in order to make room for wide receiver Willie Snead on the 53-man roster roster.
The 49ers finished Monday’s game with right tackle Colton McKivitz shifting to left tackle, guard Spencer Burford moving to right tackle and recently acquired Ben Bartch filling in at left guard. Veteran Jon Feliciano started at right guard.
Quarterback Brock Purdy was listed as a full practice participant after sustaining his second shoulder stinger in two games. Backup Sam Darnold played the final 19 snaps of Monday’s game.
Cornerback Ambry Thomas left Monday’s game with a hamstring injury. He was slated for limited practice Wednesday. The 49ers could go with Deommodore Lenoir and Charvarius Ward, as usual, at cornerback, with Jason Verrett entering as nickel back in passing situations.
Wide receiver Deebo Samuel (neck) and defensive tackle Javon Hargrave (hamstring) also were slated for limited practice.
Defensive end Arik Armstead has missed the past three games because of foot and knee issues. It apprears he will not be available to face the Commanders, either.
Wide receiver Jauan Jennings, who sat out Monday's game with a concussion, still wasn't available to practice.
The 49ers expect tight end Ross Dwelley, running back Elijah Mitchell and linebacker Oren Burks to be available to return to action Sunday.
Here's the 49ers' pre-practice injury report for Wednesday, via Shanahan:
No practice
Ji’Ayir Brown (knee)
Jaylon Moore (concussion)
Aaron Banks (toe)
Arik Armstead (foot and knee)
Jauan Jennings (concussion)
Limited
Trent Williams (groin)
Ambry Thomas (hamstring)
Deebo Samuel (neck)
Oren Burks (knee)
Javon Hargrave (hamstring)
Full practice
Brock Purdy (stinger)
Ross Dwelley (high ankle)
Elijah Mitchell (knee)
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