Yesterday we showed the impact that an upperclassman starting quarterback can make for an SEC squad.  On average, a team can expect an additional SEC win and two or three additional wins overall if they have a junior or senior under center rather than a freshman or sophomore.  

But what does veteran leadership at QB mean for the league as a whole?  Below we've once again broken down the numbers from 2009 through 2013 -- five seasons -- to determine whether or not older quarterbacks prove problematic for SEC defenses, often viewed as the best in the land.  Schools whose leading passer for a season was an upperclassmen were classified as such and vice versa.

Our findings...

 

Season Upperclass QBs Underclass QBs Avg. Yards Allowed By All SEC Defenses
2009 8 4 330.3
2010 10 2 350.9
2011 7 5 322.5
2012 9 5 363.4
2013 10 4 379.6

 

Of course, other factors like injuries, defensive experience, scheduling and the like all play a role in the rises and falls of SEC defensive stats.  But it's hard not to see the connection between upperclass quarterbacks on offense and defenses that allow more yards per game.

The story is even clearer when comparing the points SEC defenses allowed per game from 2009 through 2013...

 

Season Upperclass QBs Underclass QBs Avg. Points Allowed By All SEC Defenses
2009 8 4 20.9
2010 10 2 23.7
2011 7 5 20.8
2012 9 5 23.2
2013 10 4 24.9

 

Again, there are a lot of factors at play, but the more upperclass quarterbacks the SEC offenses use, the more points SEC defenses allow.  Which brings us to the 2014 season.  As of today it appears that at least nine SEC schools will start the season with upperclass quarterbacks.  It's possible a 10th will win his quarterback battle as well:

 

Alabama -- Jacob Coker, jr

Arkansas -- Brandon Allen, jr

Auburn -- Nick Marshall, sr

Florida -- Jeff Driskel, jr

Georgia -- Hutson Mason, sr

Kentucky -- Patrick Towles, so (or Drew Barker, fr or Reese Phillips, fr)

LSU -- Brandon Harries, fr (or Anthony Jennings, so)

Miss. State -- Dak Prescott, jr 

Missouri -- Maty Mauk, so

Ole Miss -- Bo Wallace, sr

S. Carolina -- Dylan Thompson, sr

Tennessee -- Justin Worley, sr (or Joshua Dobbs, so)

Texas A&M -- Kenny Hill, so (or Kyle Allen, fr)

Vanderbilt -- Stephen Rivers, jr (or Patton Robinette, so or Johnny McCrary, fr)

 

​You'll note that a number of those upperclass quarterbacks would either be new starters or struggled as starters last season.  Fair enough.  But there were some similar circumstances in each of the five seasons we examined above, too.

Our final verdict is simple -- SEC defenses might not allow the whopping 24.9 points per game they did a year ago, but if nine or 10 upperclassmen wind up leading their schools in passing yards, expect the league's defenses to once again struggle.  Compared to other leagues, the SEC will probably still look good defensively.  But history suggests this year's defenses won't stack up well with some of the SEC's more dominant seasons.