SANTA CLARA -- Kenneth Acker became the fourth defensive back selected by the 49ers in this draft, with the SMU product coming off the board in the sixth round at No. 180 overall.

Acker (6-foot) was a three-year starter for the Mustangs, and he totaled three interceptions and 13 pass breakups while starting all 12 games last season. He played defensive back and quarterback at Grant High School in Portland, Ore.

The 49ers' other additions to their secondary this draft include Jimmie Ward (first round), Dontae Johnson (fourth round) and Keith Reaser (fifth round).

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