AA Run Environments: The Metes and Bounds of The Southern League

Southern_League_Main_Logo_ColorAfter a brief hiatus, we move on to Double-A run environments. If you are just joining, we are taking a look at a few measurables for all the full season minor leagues to get an idea of how they compare to the big leagues. The goal is to go a step beyond typical characterizations as pitchers’ or hitters’ leagues. We have found to this point that aside from the California League and its prolific scoring, runs per game across levels are fairly similar to the major leagues. Homerun rates, on the other hand, diverge wildly between leagues.

The jump to AA is often referred to as the most difficult for prospects on their way to the bigs. The average age of players is about twenty-four and a half, over a year and a half older than those in High-A. The level consists of three leagues: the Eastern League, Southern League, and Texas League. The Cubs’ affiliate since 2007 has been the Tennessee Smokies of the Southern League. Of the three leagues, my sense is that the only one considered to be an extreme environment is the Texas League for offense.

The Run Environments

Methodology is here.


The AA levels play much closer to one another in terms of runs scored than the High-A levels. The Texas league does indeed come out on top, though the gap seems to have narrowed somewhat in recent years. Interestingly, homerun rates in the TL have increased over that time period,


though that has oscillated a bit in the past. On the whole, the Double-A levels show only a slight bump in homerun per contact as compared to High-A (2.87% AA vs 2.75% A+, 2011-2013 three year averages), though I suspect that the real jump in power is higher than that. It’s tough to disentangle the numbers from their environments, and the Cal League drives up rates at A+ quite a bit.

The Southern League Split

What originally prompted this series was a discussion of the run environment in the Southern League. I was under the impression that it was slightly hitter-friendly, which was quite clearly wrong. There are a few mentionable caveats, however. First and perhaps most importantly for Cub fans, the Smokies play in one of the best hitters’ parks in the league.  Moreover, the league features a significant divisional split. The Southern North and Southern South generate similar runs per game (4.32 vs 4.25, 2011-2013 three year averages), but diverge significantly in terms of offensive power output. 

When considering that approximately 15-20% of a team’s schedule is made up of out-of-division road games (which are included in these numbers), the homer-split is very significant. On a per-contact basis, the North plays similarly to the Eastern League, while the South is about as homer-free as the Midwest League. 

Prior to 2012, the split was easy to understand, as the two worst hitters' parks (Birmingham and Mississippi) were in the South Division, with the two best (Tennessee and Hunstville) in the North. In 2012, though, the Carolina Mudcats moved to Pensacola and the South Division, while Birmingham was shifted to the North. Despite the early returns on Pensacola’s stadium (which seems to be homer-friendly) the split has remained, and in 2013 was larger than it has ever been. This is likely attributable in part to a new stadium in Birmingham that opened this year. Another possible cause could be increasingly insular divisional schedules. I’m not sure whether this is actually happening, as the league schedule is unbalanced*, and I don’t have the energy to look at team-by-team schedules for the last 8 years.

*The Southern League is geographically large and teams are restricted in the number of long road trips they may take, necessitating the unbalanced schedule.

Cub Affiliate Levels

For Cub prospects climbing the ladder, the Southern League provides a significantly better environment for homeruns than previous levels.


Javier Baez obviously took advantage of that this year. I look forward to seeing what Dan Vogelbach and Kris Bryant can do at Tennessee in the future.

Bonus Regional Hero-Worship Tidbit

No less than three of the ten Southern League cities are named after former president Andrew Jackson (Jacksons TN and MS as well as Jacksonville, FLA). The Tennessee club has even taken the nickname “Generals” in tribute. Regardless of opinions on the historical figure, I think we can all agree that this is a step up from their former moniker “Diamond Jaxx,” which sounds like an early-90s character-driven urban crime pic.

Since I have more to say about the level of play and this post is rapidly careening towards tl;dr territory, I’ll split out the rest into a part II.

Minor League Run Environments