The knee injury to weak-side linebacker Lance Briggs might be more severe than the Bears have indicated.

Late Tuesday afternoon free-agent linebacker Cato June was signed to a one-year contract, but he has not played in a regular-season game this year. The 30-year-old, six-year NFL veteran was cut by the Houston Texans after suffering a fractured arm in the preseason. His best position has been weak-side linebacker.

After Briggs was injured Sunday at Minnesota, he was replaced by Jamar Williams, but the Bears do not see Williams as a long-term answer. Briggs' injury was believed to have been a minor sprain, and he was walking without a limp Monday afternoon at Halas Hall, but his condition has not been updated.

Briggs was well on his way to a fifth straight Pro Bowl season with a team-best 108 tackles, 2 sacks and an interception.

The 6-foot, 229-pound June is experienced in the Cover-2 defense, having spent his first four years with the Indianapolis Colts and his last two seasons with the Tampa Bay Buccaneers. He started 73 games from 2004-08 and was voted to the Pro Bowl after the 2005 season.

In 2006, June had a career-best 142 tackles in addition to 7 tackles against the Bears in the Colts' 29-17 Super Bowl XLI victory over Chicago. He also has 12 career interceptions.

Considering that he hasn't played in a regular-season game in almost a year, it's difficult to predict how soon June will be able to help the Bears.

They already have six-time Pro Bowl middle linebacker Brian Urlacher on injured reserve with a dislocated right wrist, and strong-side linebacker Pisa Tinoisamoa hasn't played or practiced since suffering a knee injury in Week Six. Tinoisamoa has remained on the active roster, but he will likely be placed on injured reserve to create a clear a spot for June.