I have watched Miami, Washington and Detroit get shredded on the ground in the preseason. Indianapolis has looked similar the last two weeks, with opponents consistently picking up yards on the ground. Is this just meaningless preseason action between a lot of players who won’t even be starters in the regular season? Or is there some meaning here.

Specifically, if a run defense is really strong in the preseason, do those tend to be the same defenses that also play the run well in the real games? And if a run defense struggles in August, is it more likely to also struggle in the regular season?

We can look at some of the numbers. The data is there to be looked at. (And granted, we’re looking at an eclectic set of numbers – some teams that the preseason more seriously than others.)

Using standard fantasy scoring (6 for TDs, 1 for every 10 yards) I took defenses ranking in the top 25 percent in run defense in the preseason for the last five years. That’s 40 teams – all teams ranking between 1st and 8th in the 2013-2017 seasons.

We then look at the same numbers from the regular season and see that 14 of the 40 (about a third) also ranked in the top 25 percent in run defense. (I’ve got those teams in bold.) Only four defenses, meanwhile, ranked in the bottom 25 percent in run defenses (tagged with dots).

So some correlation there.

GOOD PRESEASON RUN DEFENSES
YearTeamPreRnkYardsTDPtsRnk
2013Detroit8.011,5961013.78
2013San Francisco8.821,626411.73
2013Houston9.131,9581116.418
2013Seattle9.741,5351113.77
2013Cleveland10.351,7811316.015
2013Kansas City10.961,923915.412
2013New England10.971,7861115.311
2013NY Giants11.481,7431215.413
2014Washington8.411,7221114.913
2014• NY Giants8.822,1621519.129
2014Baltimore9.331,412811.84
2014Detroit9.741,10989.91
2014Denver10.251,276911.43
2014Miami10.461,9371317.022
2014Buffalo11.271,7031014.412
2014Carolina12.081,7921416.519
2015• Seattle11.572,0202020.132
2015Green Bay8.711,9051316.821
2015Buffalo9.321,7301014.615
2015Washington9.731,9621016.019
2015San Francisco10.941,3041011.93
2015New Orleans11.051,580812.98
2015Arizona11.461,460912.57
2015Denver11.881,3371012.14
2016Philadelphia6.211,6521014.111
2016NY Jets9.021,5811114.09
2016Baltimore9.831,4301012.75
2016• Washington10.641,9161919.129
2016Kansas City10.851,9381015.918
2016• Buffalo10.962,1302121.231
2016Tennessee11.071,4131012.63
2016NY Giants11.181,4171012.64
2017Cleveland7.311,5661415.014
2017San Francisco8.621,8241416.722
2017Green Bay9.131,7931015.011
2017Baltimore9.741,7801215.616
2017Chicago10.651,7301014.610
2017Dallas11.361,664713.06
2017Atlanta11.471,665913.89
2017NY Jets11.581,8871316.723
2018NY Jets7.81????
2018Baltimore8.02????
2018Tennessee9.13????
2018Pittsburgh9.54????
2018NY Giants10.15????
2018New Orleans10.76????
2018Chicago11.37????
2018Oakland11.88????

This isn’t Holy Grail type stuff, but there’s also some correlation going the other way.

Look at the 40 worst preseason run defenses of the last five years. Only seven of those defenses flipped and ended up putting up top-8 numbers in the real games. But 13 of 40 (again, about a third) continued to struggle in the regular season, ranking no higher than 25th in run defense.

BAD PRESEASON RUN DEFENSES
YearTeamPreRnkYardsTDPtsRnk
2013• Jacksonville26.3322,1082020.731
2013Philadelphia25.4311,6681214.910
2013Carolina20.6301,391410.21
2013• Tennessee20.4291,7952119.128
2013Buffalo19.6282,0631016.620
2013Minnesota18.9271,7671416.317
2013Miami18.4261,9981417.723
2013Oakland18.3251,7271516.419
2014Dallas27.8321,6501817.124
2014Pittsburgh24.1311,605913.49
2014San Diego22.0301,9861116.520
2014Chicago21.7291,8031215.815
2014Kansas City19.6282,036414.210
2014NY Jets19.5271,4891013.18
2014• Jacksonville17.4262,0331518.327
2014• Cincinnati16.9251,8611617.625
2015Baltimore23.4321,6611014.113
2015Pittsburgh21.7311,459611.42
2015Tampa Bay18.7301,6061214.514
2015New England18.6292,0711217.424
2015Philadelphia18.6282,1531017.223
2015Houston17.4271,5971013.711
2015• Indianapolis17.4261,9521417.525
2015• Dallas17.3251,9341618.130
2016San Diego26.9321,5672017.323
2016• Oakland24.9311,8811818.525
2016• Miami22.7302,2471218.526
2016• Cleveland21.1292,2831821.030
2016• Denver18.3282,0851518.727
2016Dallas18.2271,336911.72
2016• Seattle17.6262,6542526.032
2016Jacksonville17.2251,7031717.021
2017Carolina25.4321,409711.43
2017LA Chargers24.4312,0981117.224
2017New Orleans22.7301,836613.78
2017• Detroit19.5291,8001818.029
2017Miami18.4281,7681416.320
2017Jacksonville16.4271,860915.012
2017Denver16.3261,430912.35
2017• Washington15.9252,1461318.331
2018Miami31.432????
2018Washington21.731????
2018Jacksonville19.130????
2018Detroit18.729????
2018Minnesota18.428????
2018Cincinnati18.127????
2018Dallas17.926????
2018Green Bay17.925????

Collectively as a group, the 40 best run defenses of the last five years in the regular season allowed an average of 1,694 rushing yards, with 11.2 TD runs. The 40 worst run defenses allowed 1,838 yards on average, with 12.9 TDs.

—Ian Allan