Hyde had been dealing with an apparent stress fracture in his foot suffered in Oct. 11's loss to the New York Giants. He played on the injury the last two games against the Ravens and Seahawks, running for 95 yards on 31 carries combined without scoring a touchdown.
The 49ers said the team's medical staff met with head coach Jim Tomsula following Friday's practice and said Hyde would not be made available to play. He did not practice all week.
Before being ruled out, Tomsula said, "We're expecting (the decision) to go all the way up to game time. That's just the way we plan. (Hyde's) got all his assignments, in all the meetings, the walk-thrus, the practice.
"He's doing all those things. So, and then the medical staff is just letting me know that it could go all the way up to game time. So we just prepare like we're ready to go and all the other guys are ready to go and that's just how we're working through our business."
When asked if he's been told of Hyde would eventually require surgery on the foot, Tomsula said the team's medical staff has not told him that.
Tomsula on Friday indicated Bush had overtaken Hayne as the team's primary punt returner.
"Yeah. I mean, we can say that, but we've got a few guys that we're rolling through there," Tomsula said.
49ers injury report:
OUT: Carlos Hyde (foot)
QUESTIONABLE: Anquan Boldin (hamstring)
PROBABLE: Alex Boone (shoulder, knee), NaVorro Bowman (shoulder), Ahmad Brooks (shoulder), Tony Jerod-Eddie (not injury related), Colin Kaepernick (right hand), Erik Pears (back), Eric Reid (chest), Joe Staley (shoulder)
Rams injury report:
OUT: DE Chris Long (knee)
QUESTIONABLE: DE William Hayes (thigh), RB Tre Mason (ankle), S T.J. McDonald (shoulder), DE Robert Quinn (knee)
PROBABLE: DT Nick Fairley (illness), TE Lance Kendricks (thumb), LB James Laurinaitis (elbow)
Chris Biderman is the Editor-in-Chief of Niners Digest and covers the 49ers from their headquarters in Santa Clara. Chris has been writing about the team since the spring of 2013. The Ohio State alum received his Journalism degree in 2011 and has been working in sports media since 2008. Chris, a Santa Rosa, Calif. native, is also a contributor to the Associated Press covering sports throughout the Bay Area. You can follow Chris on Twitter here.
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