SANTA CLARA -- Craig Dahl will draw the start at free safety and Demarcus Dobbs will take the place of injured defensive tackle Justin Smith in the 49ers' exhibition opener Thursday against the Denver Broncos, defensive coordinator Vic Fangio said.
Dahl has been a part of the four-way competition for the starting job with rookie first-round pick Eric Reid, C.J. Spillman and Trenton Robinson.
"We'll go back to the way we started camp," Fangio said. "It's been split kind of equally between all four guys. Dahl had the first few days, he'll get the first few plays in the game."
All three players are expected to see similar playing time against the Broncos as the 49ers continue to evaluate the position.
Smith hasn't practiced recently because of a finger injury.
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