Why Nickel Defense's NFL Popularity Is Growing to Combat 'Passing League'

The NFL has reversed the trend of a long tried-and-true saying in sports: Defense wins championships. 

Last season the Green Bay Packers finished with the league's worst overall defense and not only made the playoffs, but also finished with the best record.

The Packers are the only team in the history of the NFL to accomplish the latter feat. 

Want to know who was right there beside the Packers, ranking 31st in overall defense? None other than the eventual Super Bowl-losing New England Patriots.

And the Super Bowl champion New York Giants finished the season ranked 27th in total defense.

How did these teams finish offensively? All three teams fielded top-10 offenses led by their passing games. The Packers had the third overall offense, Patriots were second and the Giants were eighth (fifth in passing offense).

The NFL is a passing league, ladies and gentlemen, and the old vestiges of defense and running the ball have been tossed aside.

According to a little research on Pro Football Reference, this past season saw the most passing attempts in league history, most passing yards and the highest average league-wide quarterback rating.

Obviously, rule changes protecting quarterbacks and wide receivers have had a major impact on how well defenses can perform. 

One thing defenses have done is become much more heavily focused on having nickel-package defenses on a weekly basis to combat three-receiver sets utilized by opposing offenses.

It's getting to the point that nickel cornerbacks are becoming the 12th starter on defense for some teams.

For those who are unaware of what the nickel defense is, it is a defensive formation that takes one of the team's linebackers off the field and replaces him with a fifth defensive back.

The formation is typically employed to defend against three or more receiver sets or a strong receiving threat at tight end.

Passing yards per game has grown by just over 37 percent since 1970. That year, passing yards per game registered at 161.4.  The NFL reached a low of only 140.9 passing yards per game in 1973, but things started to change in 1979.

In a three-year period from 1979-1981, passing numbers skyrocketed from 158.8 yards per game in 1978 to 180.4 the next year and 204.4 by 1981.

By 2006, those numbers remained largely unchanged at 204.8 ypg, but the last few years have again shown noticeable increases since 2006 from 204.8 to 214.3, to 211.3, to 218.5, to 221.6 and 229.7 in 2011.

It's no coincidence that since 2008, NFL teams have used the nickel package on 31 percent, 34 percent, 34 percent and 40 percent (2011) of their defensive snaps, according to Pro Football Focus.

If we add in the percentage of plays with six-plus defensive backs on the field last season, there were at least five defensive backs on the field for 53 percent of team snaps last season.

The New York Giants led the way in that category with a whopping 75 percent of their defensive snaps being with five-plus defensive backs.

The ability to cover receiving threats has clearly become a major point of emphasis and concern over the last few years, but until teams figure out how to slow down these pass-happy offenses in the league today expect to see more "huck it, chuck it" football in 2012.