You Shall Not Pass

Last week we took a look at run defenses, and concluded that Rutgers isn’t the steaming pile of hilarity we’re all expecting. This week, we’re taking the same look at pass defenses. Spoiler alert: Rutgers IS the steaming pile of hilarity we’re all expecting. If not steamier and… uh… more pile-like. The question at hand is as follows: who will have the best pass defense in the Big Ten in 2014?

If you’ve forgotten, we’re just taking a simple two-step process: we look at how good teams were last year at a thing, and we look at attrition among the folks responsible for the thing. Our key assumptions are as follows:

• Experience is good and, all other things being equal, makes things better than they were.

That’s it.

Were they good last year?

Again, this is the easier piece.

Yards per attempt allowed, adjusted for sacks: YPA is generally considered the statistical gold standard for overall goodness of passing games, so it is a pretty useful stat for demonstrating pass defense (It is almost certainly superior to cumulative stats. Yards per game can be misleading based on differing numbers of attempts; Purdue was middle of the pack in terms of YPG allowed, but that’s only because they faced fewer passes because their run defense was so ungodly atrocious, and they were usually behind, so offenses didn’t really feel the need to throw the ball).

We've adjusted for sacks, counting a sack as a pass attempt, which makes sense because if you drop back five times, and complete one pass for 10 yards while getting sacked four times, your yards per attempt should really reflect the fact that attempting to pass went poorly most of the time.

Passing S&P+ Defense: Click the link for a thorough explanation, but it is an advanced statistical model analyzing what defenses allow on a given play against what you would expect. Advantages are that it takes opponent strength into account, it factors in sacks, and it filters out garbage time. Numbers are national rankings.

20+ yard passing plays per game: Completions happen. A team will often gladly offer an opponent a 10 yard completion on 3^rd and 17. But 20+ yard completions are a strong indication of a pass defense prone to breakdowns, and one that cannot do the thing it is trying to do.

Sacks per game: Sacks can be either a cause of good pass defense or a symptom of good pass defense. A quality pass rush will lead to better defensive results when the opponent tries to pass the ball (see: Nebraska and Ohio State), and solid coverage will lead to more chances for the pass rush to get home with “coverage sacks” (see: Michigan State). It’s hard to separate the two causal possibilities, but for our purposes we don’t need to. They’re both good.

Putting it together

Here is how the teams shake out in rough order of how they fared in the above categories, with emphasis on the first two categories.

Like last week the teams generally break out into four tiers:

• MSU – MSU.
  • Again, they get their own tier because obviously.
• Pretty Good – Iowa, Wisconsin.
  • Great YPA numbers, minimized big plays, didn’t get home much on pass rush.
• Meh-Penn State, Maryland, Ohio State, Michigan, Nebraska, Northwestern, Minnesota.
  • The great undifferentiated mass of mediocre pass defenses. All allowed between 5.87 and 6.30 YPA (other than Maryland, who played a weaker schedule last year). All but Northwestern had S&P+ pass rankings between 41st and 64th.
• Butt (NJB)– Purdue, Rutgers, Indiana, Illinois.
  •  If you’re curious, all four of these teams performed comparably with, and perhaps even worse than, Michigan’s 2010 pass defense.

[AFTER THE JUMP: Attrition tolls for thee. If thee be Ohio State or Nebraska]

How much do they return?

As with the front seven, determining how many starters a team returns is tricky. Nickelbacks may no be “starters” per se, but they often play a significant number of snaps (and the snaps they play are disproportionately passing downs). If you look at a team like Michigan State, who is likely to replace a graduating strong safety (Isaiah Lewis) with their primary nickel defender (RJ Williamson), does that move mean they lose one starter from the secondary? Two? Zero? Hell if I know. Also, linebackers play a large role in pass defense, especially in zone-heavy systems. So what I'm saying is that this is grain-of-salt stuff.

To give a very rough estimate of what the secondary for each team is losing, I include the total number of Passes Defended (Interceptions plus PBUs) for the departing starters. Passes Defended isn’t a perfect stat (corners will usually accumulate more than safeties), but it’ll give you a general sense.

Overall, a remarkable number of defensive backs return conference-wide this year (nearly 70% of starters, compared to the roughly 63% from the front seven) The teams generally fall into two categories: minimal attrition (the first ten) and “uh oh” (Iowa, MSU, Ohio State, and Nebraska).

So, who are the contenders for Best Pass Defense in 2014?

Contenders based on returning talent

Wisconsin

• 5.54 YPA
• #28 S&P+
• 3 starters returning

Wisconsin was good last year despite being very young. They only lose safety Dezmen Southward, and they return a budding star in Sophomore Sojourn Shelton. However, they will be under more pressure this year because the entire freeking front seven.

Penn State

• 5.87 YPA
• #48 S&P+
• 3 starters returning

Corner Jordan Lucas and safety Adrian Amos will be among the best in the conference. If they can cut down on the big plays, and if the secondary stays healthy (depth is a concern everywhere other than Tight End in Happy Valley), they could be really good.

Michigan

Please continue to exist in this physical plane

• 6.15 YPA
• #54 S&P+
• 3 starters returning

Michigan loses Thomas Gordon, but if they can find a safety (cough cough JABRILL PEPPERS), they return a lot of experience at corner. The emergence of Jourdan Lewis along with Blake Countess and Raymon Taylor gives Michigan a lot of quality depth. This COULD be the year in which Never Forget is finally forgotten. At which point we will have succeeded. Or failed. I’m not sure.

Minnesota

• 6.30 YPA
• #47 S&P+
• 3 returning starters

Minnesota is a bit of a sleeper, and frankly I'm not sold, but they had a solid-ish season last year, and Eric Murray and Michael Caputo are… above average? We’ll go with above average.

Maryland

• 5.57 YPA
• #64 S&P+
• 4-ish returning starters

They suffered a number of injuries last year, but as a result a bunch of guys got experience. WIll LIkely is only 5’7”, but is probably their best DB (as well as the player with the easiest-to-pun-upon name on the roster). If their pass rush can remain as good as it was, they should be able to make the leap to the B1G without much regression.

Contenders based on don’t poke the bear

Michigan State

Unnamed Michigan State football player

• 4.40 YPA
• #1 S&P+
• 2 returning starters

They lost a first-round corner in Darqueze Dennard and a multi-year starting safety Isaiah Lewis. So maybe they take a step back. But if you expect me to denegrate them in this space, you are insane. Trae Waynes is a potential first-round talent at corner, and starting nickel RJ Williamson battled Lewis for the starting spot two years ago and will be just fine at strong safety. Also they have a free safety whose name escapes me, but I've been told he is pretty good.

Pretenders

Northwestern

• 6.08 YPA
• #73 S&P+
• 4 returning starters

Not really sure what to expect from Northwestern. They return every starter, including the starting corner they lost in the opener last year (Daniel Jones, because Northwestern has more Joneses than Ohio State has Browns). But they weren't THAT good last year, and they haven't finished in the top 40 in S&P+ pass defense in the last decade.

Purdue

• 7.10 YPA
• #76 S&P+
• 3 returning starters

I consider it a kind deed to put Purdue this high. They lose Ricardo Allen, and they return a large pile of whatever. They won't be embarassing. Happy?

Iowa

• 5.11 YPA
• #13 S&P+
• 2 returning starters

I’m a bit out on a limb here. Iowa was the second best pass defense in the conference last year, and they return two solid pieces in safety John Lowdermilk and corner Desmond King. However, they lost free safety Tanner Miller and corner BJ Lowery. They also lost their entire linebacking corp, which racked up 6 INTS. 

Nebraska

• 5.92 YPA
• #41 S&P+
• 1 returning starter

They were pretty good in the back end last year, but they lose both starting corners and a free safety, and most of their production in the process. Strong safety Corey Cooper may be able to plug some leaks, but they won't be as good this year.

Not even pretending

Ohio State

• 6.01 YPA
• #61 S&P+
• 1 returning starter

Take a mediocre (at best) pass defense and remove a first round corner and any whiff of safety experience. Okay, maybe that's poor phrasing. If there's one thing Ohio State has, it's whiffs. Lots and lots of whiffs. Ohio State allowed 143 passing plays of 10+ yards, 14 more than anyone else in the conference (Indiana, obv.). They allowed 7 pass plays of 60 (!) yards or more. Sounds like Springfield's got a discipline problem.

Rutgers

• 7.00 YPA
• #99 S&P+
• 3 returning starters

If you could distill the very essence of Gary Nova and spritz it onto a defensive secondary like MiracleGro, you would have the Rutgers secondary.

Indiana

• 7.71 YPA
• #100 S&P+
• 3 returning starters

You see, the schematic problem with Indiana's pass defense was...

Even Notre Dame be like, "man, that's poor coverage on Jeremy Gallon"

...yes.

Illinois

• 7.67 YPA
• #108 S&P+
• 4 returning starters

They surrendered 25 passing TDs. They had 3 interceptions. They defended 31 passes on the season... AS A TEAM. Even on a terrible defense Tim Bennett defended 21 by HIMSELF. They are bad. We should get to play them. That would be more fun.

Projections based on flimsy analysis

Again, the strictures require me to make a prediction. Gun to my head, I'd ask "why are you putting a gun to my head for THIS?" but if pressed I'd give the following order for 2014:

1. Michigan State
2. Penn State
3. Michigan
4. Wisconsin
5. Maryland
6. Iowa
7. Minnesota
8. Northwestern
9. Nebraska
10. Ohio State
11. Purdue
12.  
13. Indiana
14.  
15.  
16. Illinois
17.  
18.  
19.  
20.  
21.  
22. Rutgers