49ers' Lawson out for season with injury

Linebacker Manny Lawson will miss the rest of the San Francisco 49ers' season after tearing a ligament in his left knee.

Lawson, a starting outside linebacker in the 49ers' 3-4 defensive scheme, went down with the injury during Wednesday's practice. The injury didn't initially appear to be serious, and Lawson rode on a stationary bike for the rest of the team's workout.

But tests determined Thursday that Lawson tore his anterior cruciate ligament.

Lawson is second on the team with 14 tackles, showing impressive improvement from his rookie year. He started 11 games last season after San Francisco chose him with the 22nd overall selection, making 65 tackles and 2 1/2 sacks.

Veteran Hannibal Navies and seldom-used second-year pro Parys Haralson are the top candidates to replace Lawson.