49ers on Thursday: Sherman insists injuries won’t determine playoff fate

SANTA CLARA — Call it “Injured Reserve Week” at the 49ers headquarters, where players are getting ruled out daily for their upcoming playoff run.

The 49ers’ injured-reserve count features 15 players with Thursday’s addition of tight end Garrett Celek (back), following the leads of wide receiver Marquise Goodwin (foot, knee) on Tuesday and center Weston Richburg (knee) on Wednesday.

Come Saturday, nose tackle D.J. Jones (ankle) also will go on IR, and, in return, they likely will summon 2018 draft pick Kentavius Street off IR for his NFL debut as Jones’ replacement.

Injuries quickly derailed the 49ers’ past two seasons under coach Kyle Shanahan. These NFC-leading 49ers (11-2) insist they won’t let this recent injury bug strike them down. Next up is Sunday’s home game against the Atlanta  Falcons (4-9).

“I don’t think this small bit of attrition will be a determining factor,” cornerback Richard Sherman said. “We still have a standard that every guy needs to uphold.”

Rather than add Sherman to that season-ending IR list, the 49ers are playing it safe and likely will keep him out Sunday. He hasn’t practiced this week because of a hamstring strain that forced him from Sunday’s 48-46 loss. Same goes for defensive end Dee Ford.

Sherman looked spry in Thursday’s individual conditioning, and although he felt “great” in reaching 20 mph, he noted that coach Kyle Shanahan and the medical staff figure to inactivate him. “Kyle and them are more cautious than I am,” Sherman said. “I’d play in this game.”

Instead, Emmanuel Moseley will replace him, just as center Ben Garland replaces Richburg, strong safety Marcell Harris replaces Jaquiski Tartt, and on and on it goes, stretching back to Dre Greenlaw replacing Kwon Alexander after the middle linebacker’s pectoral tear on Halloween.

That’s when the hits began coming on a weekly basis, after early-season woes took out running back Jerick McKinnon, tackle Shon Coleman, wide receivers Jalen Hard and Trent Taylor and cornerback Jason Verrett.

“We can weather any storm with the guys that we have,” Sherman said, specifically of the wounded secondary, “and up front we have monsters and more guys that are going to step up and get more opportunities.”

“It’s unfortunate to have injuries and guys dropping like flies, but it’s next guy up,” defensive tackle DeForest Buckner said. “The past couple years, it happened to us early on. We’ve been lucky not to have crazy, crucial injuries at the beginning of the season, but it’s happening now. We need guys to step up and handle their business.”

Celek, 31, had no receptions in five games this season after coming off the physically-unable-to-perform list. He is an eighth-year veteran and the 49ers’ second-longest tenured player behind Joe Staley.

The 49ers filled Celek’s spot by promoting practice-squad tight end Daniel Helm (6-foot-4, 225 pounds). He had two catches in exhibition action after getting claimed off waivers from the Los Angeles Chargers. He will wear No. 43.

STREET READY: Street, a fourth-round pick, says he is “completely back to normal” and recovered from a torn anterior cruciate ligament he sustained in a pre-draft workout last year. That injury put him on IR as a rookie, and a follow-up procedure in late August had the 49ers shelve him in Week 1 as a short-term IR candidate this year.

Said Street: “It was the plan all along just to be patient and be prepared, because in a season, injuries happen all the time. Low and behold, it happens.”

Street’s 6-foot-2, 287-pound frame is renown for its power. What ability his right knee’s agility as an interior run stuffer?

“It’s more confidence for him,” defensive coordinator Robert Saleh said. “His leg is stable. … For him, when he gets around bodies, (he needs) to trust that everything’s fine and to translate his drill work to the field.” A setback Friday or Saturday likely would prompt the 49ers to promote defensive tackle Kevin Givens from the practice squad.

Street acknowledged his patience was tested as he waited to start his “dream job,” and that he’s up to the timely task for a high-stakes entrance. Said Street: “I talked to my mom about this yesterday: it’s not so much like a load being put on my shoulder, it’s more humbling about the confidence they have in me. I’m ready to go out and sell out for them.”

FUMBLE FUN: The 49ers lead the league with 19 forced fumbles, and they’ve forced at least one in five consecutive games for the first time since 2013.

More important, the 49ers are recovering those fumbles, and DeForest Buckner accounts for 4 of 13 fumble recoveries. Buckner’s four recoveries are the 49ers’ most since Ronnie Lott had four in 1988, and Buckner ranks behind only league-leader Vonn Bell’s five for the New Orleans Saints.

“When you run to the ball, good things happen,” Buckner said. “Last year, we knocked a bunch out but we could never recover them. Being able to have those four fumble recoveries under my belt, it’s nice to have.”

Last year, the 49ers recovered only 5 of 9 fumbles they forced. On Sunday, Buckner made a third-quarter recovery of a fumble forced by Jones, whom Buckner bequeathed the ball to afterward as a memento. “It was a big-time play that he made and I was just so happy to be there to recover it,” Buckner said. “But that was all D.J. so I definitely wanted to give it to him.”

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PRACTICE NOTES: Tartt (ribs), defensive tackle Jullian Taylor (elbow) and cornerbacks Sherman (hamstring) and K’Waun Williams (concussion) did individual conditioning rather than practice. Not seen on the practice fields were Jones and Ford.

Safety Jacob Thieneman (6-1, 215) was signed to the practice squad. The Purdue product had stints with the New York Giants and Indianapolis Colts this past offseason.