Bronson out of Niners' depleted secondary
Bronson has started every game this season. He was hurt early in the 49ers' loss to Arizona last Sunday.
The 49ers also will be without top reserve safety Ronnie Heard, who sprained his left knee against the Cardinals.
John Keith is expected to start in Bronson's place. Keith has started six games in his four seasons with San Francisco, but began the season on the practice squad.
This story is from ESPN.com's automated news wire. Wire index
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