Colvin isn't a great linebacker. He struggled in pass coverage and was adequate against the run. However, he excelled at getting to the quarterback something the team has lacked for years. Phillip Daniels was second on the team with 5.5 sacks.
In the salary cap prediction game the team couldn't tie up approximately $30 million in Colvin when Brian Urlacher will demand the biggest contract in franchise history. The All-Pro middle linebacker will command anywhere from $40-60 million dollars with a huge signing bonus.
Bryan Knight is inexperienced, but has the potential to play a similar role to that of Colvin. He played defensive end in college and was converted to strong-side linebacker. If the Bears don't draft Terrell Suggs with the fourth overall pick then between Knight and Alex Brown the team must hope to pressure the quarterback enough to get by.
Although, if that's the case then the Bears better improve the secondary, which only had nine interceptions.