3rd (4th) and Long Defense

I have it in my mind that M gives up first downs (or TDs, sometimes both) a lot on 3rd and long plays (or the subsequent 4th down).  I decided to look it up and see if my perception is true.  I decided to use defensive plays of 3rd down and 10 or more because a) the feeling I have is how ridiculously badly the D is doing and 10 yards is a ridiculous distance to get on one critical play and b) If I used a smaller number it would take me longer to gather the data.

I was very surprised that M gave up first downs (or TDs, sometimes both) on only 2 of 7 3rd and 10+ attempts (and subsequent 4th downs) today.  It seemed like every long 3rd down was successful for the Indiana, but in fact M forced 3 punts, and twice prevented Indiana from making it on 4th down.

For the season M has allowed first downs (or TDs, sometimes both) 9 times out of 26 3rd and longs.  It is a little sad to think if the D can hold a team to no gain or loss of yardage on the first two plays of a sequence, 1/3 of the time they will allow a first down anyhow.

But, looking closer shows that 4 of these 9 were against UConn (4 of 6).  Since then, M has a 5 out of 20 rate.  The worst one for this season was today's 3rd and 19.

In second quarters this year, M's rate is 3 of 4

I don't know what all of this means.  I think it shows that M has improved since the UConn game, but still has that vulnerability.  If I have time I will compare it to some other team to see how those numbers come up.