SANTA CLARA There's a reason the 49ers have an open roster spot and were looking at a couple of veteran kickers Tuesday.
Coach Jim Harbaugh said Wednesday that David Akers is dealing with a pelvis injury and that the 49ers need a "Plan B" if he can't play Sunday at St. Louis.
That plan would be to sign either ex-Charger Nate Kaeding or ex-Raven Billy Cundiff to a short-term contract while Akers heals. Both visited Santa Clara on Tuesday and worked out for Harbaugh and special-teams coach Brad Seely.
Akers was listed as limited on Wednesday's practice participation report. However, he was observed kicking field goals at the start of practice, some from as far away as 50 yards.
Akers, in his 15th season, missed 2 of 3 field-goal attempts Sunday at New Orleans and winced after making a 27-yarder in the fourth quarter. His 70.4 percentage is his lowest since he became a full-time kicker in 2000.
The 49ers, meanwhile, put running back Kendall Hunter and wide receiver Kyle Williams on injured reserve this week, opening two roster spots.
One spot was filled by removing rookie running back Jewel Hampton from the non-football injury list. The other could be filled by promoting a player from the practice squad or by signing Kaeding or Cundiff.
Walker watches Tight end Delanie Walker, who had a game-high 81 receiving yards Sunday, sat out Wednesday's practice with a hip injury.
Walker said Tuesday the injury wasn't serious and that he expected to play against the Rams. If he can't, undrafted rookie Garrett Celek likely would see more action.
Meanwhile, two 49ers were in black, no-contact jerseys Wednesday. NFL sack leader Aldon Smith is dealing with a shoulder injury. Safety and special-teams player Darcel McBath apparently suffered a concussion Sunday. Both were limited in practice.
Amendola ailing Rams wide receiver Danny Amendola, a difficult matchup for the 49ers in the teams' first meeting, missed practice Wednesday with a foot injury.
Amendola had 102 receiving yards Nov. 11 and was too quick for 49ers cornerback Carlos Rogers. He suffered a foot injury the following week and was limited Sunday in the Rams' win over Arizona.