With apologies to my fellow NFL analysts on B/R, there's one big difference between the Chicago Bears defense of 2009 and the Chicago Bears defense of 2012 that will help alleviate the pain of Urlacher missing time.
The huge difference is in Julius Peppers and the pressure he brings from his defensive end spot. The Bears did struggle because of Urlacher's absence in 2009, but the struggle was from the lack of pressure from the front four.
Alex Brown, Adewale Ogunleye and Mark Anderson combined for exactly one QB hit during the 2009 season, according to the official Chicago Bears 2009 season in review. Those three rushers combined for 16 sacks on the season versus the 11 Julius Peppers racked up in 2011.
Forcing the Bears' hand even more in 2009 was their propensity to blitz the QB more than they have in the history of Lovie Smith's tenure. With no pass rush from the front four, the Bears blitzed 45 percent of the time during the 2009, which was a major increase over the 23 percent in 2008.
According to Football Outsiders, the Bears were back down to a 27 percent blitz rate in 2011 with Peppers in the lineup. The Bears also have a much stronger DT rotation than they had in 2009 with Tommie Harris on bad knees and two uninspired players in Marcus Harrison and rookie Jarron Gilbert.
In run defense the Bears may take a hit because it will be hard to replace Urlacher. The hit shouldn't be as big as it was in 2009 since Nick Roach is a better athlete and run defender than Hunter Hillenmeyer and is three years past that 2009 season. Roach filled in admirably for two games in 2009 but was only in his first full season as a starter for the Bears.
Roach didn't know the defense nor how to call the defensive plays, which led to him being shifted back to the SAM spot with Hillenmeyer in the middle. He is a very underrated linebacker in the Bears scheme with Urlacher and Briggs being among the best in the league.
While there is no way to truly replace arguably the greatest middle linebacker of the last decade, the Bears are far better prepared to do so than they were in 2009.
The talent level on defense has increased significantly from the 2009 season and that is being overlooked. With Henry Melton poised for a Pro Bowl season, Stephen Paea poised for a breakout season combined with Julius Peppers and the underrated Israel Idonije, the Bears defense can still be a formidable unit in 2012.