SANTA CLARA, Calif. (AP) - San Francisco 49ers linebacker Ahmad Brooks had arthroscopic surgery on his left knee Monday to remove a
small bone fragment, a procedure that likely will keep him out the team's season opener Sept. 13 at Arizona.
Brooks had an MRI exam on his knee late Sunday and it was determined he needed surgery, which was done at nearby Stanford
University. He is likely to be sidelined two or three weeks.
Coach Mike Singletary said Brooks might have initially hurt the knee in practice, then aggravated it during the team's preseason win at Dallas on Saturday night.
Brooks, a fourth-year pro in his second season with San Francisco, is a backup outside linebacker to Parys Haralson. He wasn't active for any games last season.