Acker, taken with the 180th pick, wasn't invited to February's scouting combine. He has good size, footwork and balance, according to scouting reports.
Reaser, 5-10 and 190 pounds, suffered his ACL tear in October and since had another surgery after his body rejected the cadaver graft from the original surgery. It's unclear what the 49ers' plan will be in regards to a time frame for Reaser's eventual return to the field.
"I'm just going to go with the speed of the doctors are telling me to go. I'm just going to follow the rehab protocol. If that's what they feel is best then that's what I'm going to go with," Reaser said.
San Francisco, along with a number of other teams, were intrigued with Reaser because of his speed. He said his best 40 time as a blazing 4.32, which would make him one of the fastest players on the roster should he fully recover. He also has a background in returning kickoffs.
Acker wasn't invited to the combine but was on the honorable mentions list. Because a record number of underclassmen were invited this season he as on the wrong end of the numbers game. He also spent time returning punts and kicks.
"I went out there a lot for the sure-handed guys just to make sure we got possession of the ball," Acker said. "That's something that I've doing for some years so I feel pretty comfortable doing that."
The two players join fourth-round pick Dontae Johnson and first rounder Jimmie Ward in the batch of four rookies added to the secondary in the draft.
There will be plenty of competition among the group in training camp. Aside from likely starters Chris Culliver and Tramaine Brock, the team added Chris Cook via free agency and brought back Perrish Cox along with Eric Wright on one-year contracts. Undrafted rookies Darryl Morris and Dax Swanson will also be competing for roster spots.
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