Abanikanda (coach's decision) is inactive for Thursday's matchup with the Rams, Lindsey Pallares of the 49ers' official site reports.

The running back was claimed off waivers by the 49ers on Dec. 3 with Christian McCaffrey (knee) and Jordan Mason (ankle) both injured. Both remain on injured reserve, but Isaac Guerendo, Patrick Taylor and Ke'Shawn Vaughn are San Francisco's active running backs for Thursday night. Abanikanda was inactive for each of the 12 games that he spent with the Jets this season before being waived.

Walker (calf) was a non-participant at Thursday's practice, John Boyle of the Seahawks' official site reports.

Coach Mike Macdonald relayed to Michael-Shawn Dugar of The Athletic on Wednesday that Walker still was day-to-day, and the running back's status for Sunday's game versus the Packers was up in the air. Per Dugar, Walker's lack of practice reps so far this week won't preclude him from playing this weekend if his calf is deemed able to hold up. If Walker is limited or inactive Sunday, though, Zach Charbonnet would garner a second spot start in a row, with Kenny McIntosh also on hand for reps out of the Seahawks backfield.

Taylor may not start Thursday versus the Rams with Isaac Guerendo (foot) active for the contest.

If Guerendo wasn't able to play Week 15, Taylor was lined up to be the 49ers' primary runner for at least one game. Having said that, per Matt Barrows of The Athletic, Guerendo felt good following Wednesday's limited practice, which was enough for the team to clear him. Taylor likely will cede a majority share of touches if Guerendo indeed is able to start, but the former still will be in the mix for snaps along with practice-squad call-up Ke'Shawn Vaughn. In nine appearances this season, Taylor has tallied 14 carries for 50 yards and one TD and gathered in one of two targets for 12 yards.

Guerendo (foot) is listed as active Thursday against the Rams, Lindsey Pallares of the 49ers' official site reports.

Guerendo came out of this past Sunday's win versus the Bears with a sprained foot, which left his status for Week 15 up in the air. He wasn't able to practice until Wednesday, when he was listed as limited, and both Adam Schefter of ESPN and Matt Barrows of The Athletic reported at different points Thursday that Guerendo felt good following that session and intended to play. Indeed, that has come to pass, but it remains to be seen if Guerendo will handle the majority of backfield reps for the 49ers. Patrick Taylor and Ke'Shawn Vaughn also are on hand for work at running back.

Mattison (ankle) was a full participant in practice Thursday, Paul Gutierrez of ESPN.com reports.

Mattison's full participation in practice to kick off Week 15 prep clears the way for him to put an end to his three-game absence Monday against the Falcons, but he'll likely find himself in a smaller role than he enjoyed prior to missing time with the ankle injury. Per Levi Edwards of the Raiders' official site, head coach Antonio Pierce announced Wednesday that Sincere McCormick will remain the team's starting running back moving forward, which likely means Mattison will see a reduction in the 9.7 carries per game he had averaged for the season before suffering the injury. McCormick hasn't shown much prowess as a receiver, however, so Mattison could be called upon to replace him on passing downs after averaging a healthy 9.8 yards per reception prior to his recent absence.

Demercado (back) didn't practice Thursday, Zach Gershman of the Cardinals' official site reports.

Demercado has yet to take part in drills this week due to a lingering back injury that limited him during the entirety of Week 13 prep. His lack of activity this time around may be maintenance related, but his status is one to monitor to see if he could be in danger of missing Sunday's game versus the Patriots. If Demercado is inhibited or sidelined this weekend, rookie Trey Benson would be the Cardinals' unquestioned No. 2 RB behind starter James Conner.

The 49ers elevated Vaughn from the practice squad to the active roster ahead of Thursday's game versus the Rams.

Vaughn got in the mix this past Sunday against the Bears when Isaac Guerendo exited early due to a foot sprain. All three of Vaughn's offensive snaps occurred in garbage time with San Francisco holding a massive lead, resulting in two carries for four yards. Guerendo's status for Week 15 remained in limbo until earlier Thursday, when Adam Schefter of ESPN reported that the running back "feels good" and intends to play versus L.A. If Guerendo is able to suit up, he likely would pace the team's backfield, with Patrick Taylor and then Vaughn the pecking order behind him.

Hall (knee) didn't practice Thursday, Rich Cimini of ESPN.com reports.

Though Hall did make an appearance in the injury rehab area, per Cimini, this marks the fifth straight practice that the running back has missed. Friday's final injury report will relay whether Hall has any chance to face the Jaguars on Sunday, but if he remains unavailable for the contest, Braelon Allen and Isaiah Davis would be in line to split the Jets' backfield duties Week 15.

Kamara (illness) was a non-participant at Thursday's practice, Matthew Paras of The New Orleans Times-Picayune reports.

Kamara now has opened Week 15 prep with back-to-back absences due to an illness, giving him just one more chance to mix into drills before the weekend. Friday's injury report will reveal whether or not he's tagged with a designation for Sunday's game against the Commanders. Behind Kamara, Kendre Miller and Jamaal Williams are the next players up in the Saints backfield.

Blackshear (chest) was a limited participant in Thursday's practice.

Blackshear was unable to practice in any capacity Wednesday, so it's encouraging to see his activity level increase. With Jonathon Brooks (knee - ACL) done for the year, Blackshear could see increased depth opportunities behind starter Chuba Hubbard if he's able to suit up for Sunday's game against the Cowboys.