For the 49ers’ second-longest tenured player, this may well be the end of the road.

‘Celek Time’ appears to be coming to an end, D.J. Jones to join him on IR

Only Joe Staley has spent more time with the 49ers than Garrett Celek, whose abbreviated season, which started on the physically unable to perform list due to a back injury, and lasted just five weeks, is now over.

That back injury appears to have reared its ugly head again, as Celek was limited in practice on Wednesday, and has been placed on injured reserve, while practice squad tight end Daniel Helm has been promoted to the active roster.

Celek was the third 49ers player to be placed on injured reserve this week, along with Marquise Goodwin (knee, foot) and Weston Richburg (torn patella tendon), and D.J. Jones is the fourth, as head coach Kyle Shanahan confirmed on KNBR on Thursday, with a high ankle sprain. The full list of injured reserve players is now 16 players deep, though Kentavius Street is expected to come off the IR list and replace Jones on the active roster on Saturday:

LB Kwon Alexander (torn pectoral)

DE Ronald Blair III (torn ACL)

TE Garrett Celek (back)

T Shon Coleman (torn ACL)

WR Marquise Goodwin (chronic knee, ankle issues)

CB Tim Harris (groin)

WR Jalen Hurd (stress reaction, back)

OL Andrew Lauderdale (quad)

RB Jerick McKinnon (knee, complications with ACL recovery)

DE Damontre Moore (fractured forearm)

WR Shawn Poindexter (torn ACL)

C Weston Richburg (torn patella tendon)

DE/DT Kentavius Street (knee arthroscopy, after ACL recovery complications)

WR Trent Taylor (foot fracture complications)

CB Jason Verrett (knee)

Sherman says he could play this week if needed

All three of Jaquiski Tartt, K’Waun Williams and Richard Sherman were on the sidelines, not in uniform, but all three were doing some sort of conditioning work. Sherman’s is obviously the most notable in the Tartt’s injury (rib fracture) is more about pain tolerance and Williams’ concussion is a matter of time and mental and physiological recovery.

But Sherman was more active than he appeared to be on Wednesday, when he was doing slow, sort of walking-paced stretches and exercises. On Thursday, despite his knee strain and hamstring strain, Sherman at points ran at near full-speed, a sign of optimism for a player Kyle Shanahan said he expected to be out a couple weeks on Monday.

Sherman, however, said that he could play this week if necessary, and that this injury isn’t nearly as bad as the pain he was in prior to facing the Green Bay Packers.

Sherman says coaching staff is being extra cautious with his hamstring injury: “I could play this week if we had to have it… I ran 19-20 miles per hour today.” pic.twitter.com/outfyLFa4v

— KNBR (@KNBR) December 12, 2019

Tartt told KNBR that his rib injury isn’t just a pain tolerance issue, but it’s range of motion. He can’t lift his arms or hit in the way that’s necessary to practice or play in a game as of yet. He’s situation is still day-to-day.

Jullian Taylor was also in the area with his jersey on, with his right elbow swaddled in an arm brace. He appeared to be doing some basic conditioning work, but is not expected to play this week.