SANTA CLARA, Calif. -- Veteran San Francisco linebacker Jeff Ulbrich won't play again this season because of a concussion.
He might be done altogether.
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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. He acknowledged he needs to think about his long-term health, future and family.
"We really have a conservative approach in everything we do as it pertains to our players," Singletary said. "We want to make sure that even though we come out here and we stress the physicality of what we're trying to do and what we're trying to bring across, at the same time on the other side of that we want to make sure we take care of our players. Because taking care of the players means we're taking care of their families as well, in the long run."
Ulbrich's presence will be missed, even if he's still around in a different role. He's one of the longest-tenured 49ers.
"I give a lot of credit to him. He's a barbarian of the game," fellow linebacker Patrick Willis said. "I dress next to him. There are some days that I'm not feeling 100 percent and maybe I don't feel like practicing. But then I see him and Takeo (Spikes), and I think, 'Those two old guys can do it, I can do it, too."'
The 49ers filled Ulbrich's spot on the 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.
Singletary plans to keep Ulbrich involved in team meetings and practice. He also might travel to some road games.
"A guy like Jeff, knowing Jeff, he's never going to be in total agreement, because he's a football player," Singletary said. "It's easy to sit down and say, 'You know what, I may consider retirement,' but when it really comes down to it and it's actually a possibility now it's like, 'Wait a minute, hold on, I didn't sign up for this part of it.' I think in the end he knows we have his best interest at heart and to look down the road he's had a heck of a career. Right now that's where we see it and we just want to do what's best for him."
Singletary said it's unlikely strong safety Michael Lewis will go on IR despite suffering three concussions this year, including two in an 11-day span during the preseason. Singletary said Lewis responded and recovered quickly after his latest concussion Oct. 11 against the Rams.
Lewis also has undergone extensive testing and Singletary expects to know more about his situation in the next day or two.
"As of right now the early prognosis is that he's OK," Singletary said. "We'll have to monitor that going forward. I want to listen to what they tell us after the testing and make decisions going forward."
The 29-year-old Lewis, a Pro Bowl selection in 2004 with Philadelphia, is in his eighth NFL season and third with San Francisco. He ranked third on the team with 118 tackles in 2008.
Lewis recently expressed concern about his concussions and the susceptibility to having more considering his pattern.
Lewis' first concussion occurred Aug. 18 during a joint practice with Oakland at the Raiders' training site in Napa when he got hit by a fullback. He suffered another in an exhibition game at Dallas on Aug. 29, when he fell and took a knee to the helmet.
Copyright 2009 by The Associated Press