While the Buffalo Bills have pretty much the same corps of players on the offensive side of the ball returning from the 2011 season, the defensive side of the ball is vastly improved. There have been some new draftees, free-agent signings and those returning from injury will assume a starting role heading into the 2012 campaign.
General manager Buddy Nix orchestrated one of the most successful offseasons in recent memory, putting the Bills in a great position to recapture the AFC East title they had often dominated in the early '90s.
However, if the injury bug strikes again or players just aren't performing up to standard, there are certain guys who will need to step up in order for the Bills to have a successful season.
Here are five backups who will play key roles in 2012.