SANTA CLARA, Calif. (AP) -Veteran San Francisco linebacker Jeff Ulbrich won't play again this season because of a concussion.

The 49ers placed the 32-year-old Ulbrich on injured reserve Monday, ending his season. He sustained a concussion on the opening kickoff against St. Louis on Oct. 4 and was examined by a neurologist last week. Coach Mike Singletary said Monday the team concluded it was in Ulbrich's best interest to go on IR.

The 10th-year pro, who is away from the team this week handling personal business, has said he's not ruling out retirement after sustaining more concussions during his career than he can count.

The 49ers filled Ulbrich's spot on the active roster with linebacker Matt Wilhelm, who was in training camp with the Philadelphia Eagles this year before being released. The 28-year-old Wilhelm spent the 2003-08 seasons with San Diego.