SANTA CLARA -- As the 49ers have staggered to a 4-10 record, coach Jim Tomsula said Monday he sees some bright spots with a developing core of young players.
The 49ers lost a huge chunk of their core roster that led them through three consecutive trips to the NFC Championship game and one Super Bowl appearance under coach Jim Harbaugh.
But from the end of last season until the beginning of this year, such players as Frank Gore, Patrick Willis, and Justin Smith did not return.
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“We knew there’s a core group that’s not here,” Tomsula said. “There was a core group here, with Justin and Frank and all those guys, there was a core group here that built up through some tough times and got into some really good times and did a heck of a job (of) leading and just the tightness.
“I don’t think we’ve hidden from that. That core is gone. We’re developing another core. We got to develop a core.”
Tomsula mentioned a young core to go along with such veterans as Ian Williams and NaVorro Bowman that includes such players as Jimmie Ward, Blake Bell, Eli Harold, Jaquiski Tartt and Quinton Dial.
“I think there are a lot of pieces to that core here,” Tomsula said. “We’ve got some here that I’m really excited about. . . Is it a welded-together core? No, not yet. But are they working towards it? Do they have the intangibles? I believe they do.”
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In other 49ers news . . .
--Center Marcus Martin was diagnosed with a concussion and must pass the NFL's concussion protocol to be cleared to play in Sunday's game against the Detroit Lions.
--Running back Shaun Draughn was scheduled for an MRI examination on his knee on Monday at Stanford. He exited Sunday's game in the first half. Rookie running back Mike Davis is eligible to return to action this week after missing six games while on injured reserve/designated for return due to a fractured left hand.
--Rookie right tackle Trent Brown got high marks for his performance Sunday after entering the game when Martin left. Tomsula said Brown must show he knows his assignments, especially how to handle blitzes and line stunts in front of him.
--Tomsula said it was his decision to get more playing time for Dontae Johnson at right cornerback in place of Kenneth Acker. Keith Reaser also saw some limited playing time.
"It’s more about those other guys than it is about Kenneth," Tomsula said.