Take Two: Will Northwestern's defense be better or worse in 2016?

Ben Goren: Northwestern's defense last year was alright. I mean, if you're into top-five S&P+ defenses who surrender fewer passing touchdowns than any other team in the nation, 2015 Northwestern was right up your alley. With playmakers on every level of the defense and (gasp) NFL talent aplenty, Northwestern had its best defensive year under Pat Fitzgerald, and probably the best defensive year since Fitzgerald was wearing a jersey himself. That squad set an awfully high bar that next year's crew has to match. It won't be easy.

Everything from simple regression to the mean to the departure of both starting defensive ends suggests the defense takes at least a modest step back. I'm not so sure that's what's going to happen. But Henry Bushnell is a pessimist and thus sees the defense getting worse. Why, Henry?

Henry Bushnell: Well you kind of just stole my thunder. There are two pretty clear and logical arguments for why the defense will be worse in 2016 than it was in 2015. One is the loss of Dean Lowry and Deonte Gibson. The other is twofold: Northwestern's defense overperformed a year ago, and its opponents underperformed. There's less evidence for this second hypothesis, simply because in football, it's tough to isolate an offense's performance from that of the defense opposite it. But between the theoretical idea of regression to the mean and the eye test, I think I can argue it.

Let's start with the defensive ends though. I don't think it's possible to overstate how important Lowry and Gibson were for Northwestern. And on a more fundamental level, I don't think it's possible to overstate how good they were. Lowry got all the love and is the more imposing physical specimen, but on multiple occasions, Gibson was the best player on the field when NU's opponents had the ball. The best player, bar none. Better than Lowry. Better than Anthony Walker. He was unblockable against Wisconsin. He wreaked havoc against Penn State. He was huge against Stanford, and was outstanding against the run all year.

I can give more specific reasons for his importance later, but the TL;DR version of everything I'll write here is that two great two-way defensive ends were integral to all the success Northwestern had on defense in 2015, and NU has nobody to replace them. So Ben, you must either think NU does have replacements, or that Lowry and Gibson weren't that important...

BG: No, you're right, the defensive ends were super good and there aren't any clear cut replacements in the pipeline. Washington and Odenigbo are both still pass-rush specialists (we think) and unless you saw something in Joe Gaziano I didn't, he's not super ready to be a huge impact player next year. In that regard, Northwestern's going to be playing a heavy dose of catch-up.

But I think Northwestern has the defensive tackles to make up for it. Jordan Thompson, C.J. Robbins and Tyler Lancaster are three legit players. There's depth behind them with Fred Wyatt and Greg Kuhar too. Northwestern's going to win the battle at the point of attack consistently next year, probably with even more consistency than it did last year. It's also not outside of the realm of possibility to move Robbins or Thompson outside in certain situations. It'll be like the inverse of the NASCAR package of the Lowry years.

I'm also super duper high on the defensive backs this year. Nick VanHoose is brutally underrated and replacing an All-Big Ten corner is never easy, but I love what the new starters in the unit bring. Keith Watkins showed out in the bowl game and is a physical dude who can lock guys up. Kyle Queiro can be played in centerfield, in the box, or in the slot and be an impact player in any of those places. Combine them with certified ballers Matt Harris and Godwin Igwebuike and Northwestern's defensive backs last year were a bend-but-don't-break unit on steroids. Northwestern ranked 39th in DB havoc rate last year. I'd be shocked and a little disappointed if that doesn't improve next season.

HB: But I think what you're missing is just how interconnected all aspects of a defense are, and how much the defensive backs benefitted from the defensive line's play last year. Even if the Harris/Watkins duo matches the VanHoose/Harris duo in terms of ability, I don't think the former will match the latter in terms of production.

The most obvious aspect of that is the pass rush. Even if that's the strength of the two ends that will replace Lowry and Gibson, Odenigbo and Washington are still more or less one-trick ponies. Sure, Purdue might not be able to stop them, but good offensive teams will. Offensive tackles will be taught to contain the speed rush. Offenses can scheme to neutralize Odenigbo's quickness off the edge. It's not exceedingly difficult.

The secondary will also have to bear more responsibility, because Northwestern's linebackers will have to hone in more on the run. Two-way players like Lowry and Gibson, even if they're not extremely talented like Lowry and Gibson, are so valuable because there are no major holes in their games that opposing offensive coordinators can look at and go, "Let's come out on our first two drives and exploit this. Then let's see what their defense sacrifices elsewhere to plug up those holes, and exploit whatever it is they sacrifice." Northwestern rarely had to sacrifice anything in 2015. In 2016, NU might have to. That's the main reason I see them regressing.

BG: You're right, the secondary and the linebackers are going to bear more responsibility than they were asked to last year. I just think that the athletes that are in those spots can handle it. The edge might not be set well with consistency next year, but I think Anthony Walker, Nate Hall, and [insert third linebacker here] have enough range and athleticism to make up for it. The pass rush might be a half second slower next year, but I trust the back end to lock guys up for that much longer.

Even without an improved Odenigbo or Washington, I expect the defense to at least tread water. If Odenigbo, the best recruit in Northwestern history (well since 247 Sports started tracking them), takes the jump we've been waiting on for a few years now, I think the defense gets even better. There's just so much dang athleticism on this unit this year. Mike Hankwitz can dial up some funky defenses to turn that speed and strength loose. It might be a really fun year to watch the Wildcats punch teams in the mouth.

HB: My last point is that teams this year won't just stand still and wait to get punched in the mouth. Northwestern played a lot of pathetic offenses last year –€” Duke, EIU, Ball State, Minnesota, Purdue, Wisconsin, Illinois. In fact, let's take a quick look at the S&P+ offense rankings of NU's 13 opponents: 5, FCS, 90, 103, 58, 32, 56, 36, 59, 84, 83, 98, 43. The average of the 12 FBS opponents was 62.25. For a schedule that appeared strong, with 10 Power Five opponents, that's notably low. The competition will stiffen up in 2016, and with a less potent front four, Northwestern's defense will take a step back, even if only a small one.