SANTA CLARA -- When 49ers defensive coordinator Robert Saleh gets the go-ahead, strong safety Jaquiski Tartt will be back in the starting lineup.

The 49ers play the Seattle Seahawks on Sunday night in a game that will determine the NFC West champion. Tartt played a key role in the 49ers’ secondary through 12 games before exiting the lineup with fractured ribs.

“It would come from the performance staff on whether or not he’s healthy to get back with us,” Saleh said on Thursday. “I know he’s been practicing and trying to get back into it. As soon as he’s ready to roll and when we get clearance, he’ll be in there.”

Defensive tackle Jullian Taylor’s status is uncertain for Sunday's game after he sustained a knee injury in practice on Thursday. Taylor missed the past three games with an elbow injury. He is expected to undergo an MRI on his knee to diagnose the specifics of the injury.

Tartt missed the 49ers’ past three games with fractured ribs he sustained while making a tackle of Baltimore Ravens running back Mark Ingram on Dec. 1. Tartt returned to limited practice this week, but Saleh said he has yet to be cleared.

Tartt serves an important role in play-to-play communications on defense, along with middle linebacker Fred Warner. Second-year player Marcell Harris has filled in for Tartt.

“The amount of calm he brings, not to say Marcell hasn’t been able to get a little bit better every single week, which he has,” Saleh said. “He’s had major strides from Game 1 to Game 2 to Game 3, but just the overall communication, the disguise, the alignments, all the things that we ask out of that strong safety, he had been on point.”

Defensive end Dee Ford did not take part in practice due to quad and hamstring injuries. He is not expected to be available for Sunday’s game, but the club expects him to be available for the team’s first playoff game.

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49ers participation report

Did not practice

DE Dee Ford (quadricep, hamstring)

Limited

LB Azeez Al-Shaair (knee)

G Mike Person (neck)

WR Deebo Samuel (shoulder)

S Jaquiski Tartt (ribs)

DT Jullian Taylor (elbow, knee)

Full participation

CB Tarvarius Moore (concussion)

Seahawks participation report

Did not practice

T Duane Brown (knee, biceps)

S Quandre Diggs (ankle)

G Mike Iupati (neck)

WR Malik Turner (concussion)

Limited

DE Jadeveon Clowney (core)

C Joey Hunt (fibula)

T Germain Ifedi (knee)

T Jamarco Jones (shoulder)

C Ethan Pocic (core)

Full participation

T George Fant (knee)

CB Shaquill Griffin (hamstring)

LB Mychal Kendricks (hamstring)

LB Bobby Wagner (ankle)

LB K.J. Wright (shoulder)