As the Detroit Lions' season winds to a disappointing close, I'm sure there will be plenty of discussion about their "Wide 9" defensive scheme and whether it should be adjusted during the offseason. My amateur take: There has been too much consternation about an alignment that often only impacts one of a team's 11 defenders.
In a nutshell, the "Wide 9" puts defensive ends in better position to get upfield by pushing them further past the last offensive player on the line of scrimmage. The alignment can cause a pronounced gap between the defensive tackle and end on the offense's tight end side, but on the backside the extra space is minimal. The defensive ends often set up in a "track position" and could angle themselves directly toward the pocket for better access to the quarterback.
If the scheme is played correctly, the defensive line gets upfield and causes havoc while linebackers fill in the gaps left over. In a worst-case scenario, the "Wide 9" creates extra-large running lanes to be exploited by the offense.
So has the "Wide 9" limited the effectiveness of the Lions' run defense this season? That's a difficult question to answer. Most football people will tell you that schemes are secondary to talent. Always and forever.
With that said, we can consider a few measurables.
The Lions have allowed opponents 4.6 yards per carry this season, tied for the fifth-highest mark in the NFL. (To be fair, they would rank No. 13 with a 4.4-yard average if the Houston Texans' Justin Forsett had been credited with a 10-yard run, rather than an 81-yard touchdown, on Thanksgiving Day.)
Second, and perhaps more revealing, is this nugget from ESPN Stats & Information: The Lions have allowed 3.0 yards per carry before first contact, the fourth-highest total in the NFL.
You could analyze that figure a number of ways. Is it because the Lions' defensive linemen aren't in position to clog those lanes? Or is it because of the Lions' broader philosophy of asking them to get upfield above all else? Perhaps the Lions' linebackers failed to compensate as required?
That's a job for the Lions' annual offseason study. In this case, we can identify the illness -- runners on average getting more yards than they should before encountering a defender -- but the cause is less clear. Is the "Wide 9" vulnerable against the run? That's a convenient and logical answer, but I'm not sure if it's right.
It isn't vulnerable when it's played well. Using the same scheme in 2010, the Lions allowed the seventh-lowest average yards before first contact (2.2). Again, scheme is always and forever secondary to players.