Spring preview: Defensive line

Wisconsin's defensive line will look very different at times in 2013 for a position where all of last year's starters are returning for another season. Beau Allen, Ethan Hemer, and David Gilbert are all entering their senior seasons, and Brendan Kelly is back thanks to an NCAA eligibility waiver.
But their roles will vary wildly with Gary Andersen running the show. Andersen and new defensive coordinator Dave Aranda want to rotate between a 4-3 defensive front and the 3-4 defense this season, meaning that the defensive line's responsibilities will sometimes change within series. But moving to the 3-4 isn't just about shifting positions- some players will be asked to do completely different things at the same position.
To be sure, it'll be an interesting transition to watch. The Badgers will start installing their new defense on Saturday when they open Spring Camp, and needless to say a few more questions will spring up after they put their pads back on. But for now, here are a few things to think about as the team starts to clear the snow off of the turf at Camp Randall.
Who plays what position?
If a team runs a 3-4 defense, they're not just lining up in different positions. The 3-4 requires a different kind of player at defensive end and nose tackle than the 4-3 does. Luckily for the Badgers, Allen seems like the kind of player who could play as the nose tackle in a 3-4 font. Allen is 6-foot-3 and weighs 335 pounds, which is probably big enough for him to demand a double team and try to fill up both 'A' gaps on either side of the center.
But fellow defensive tackle Ethan Hemer seems like a good candidate to shift over and play as a defensive end in a 3-4 front. Hemer is listed as 6-foot-6 and weighs 319 pounds, which is a pretty good size for a 3-4 end. In this scheme Hemer would be responsible for stopping the run at both the 'B' and 'C' gaps, and it seems like he has the length to occupy that much space. Warren Herring might also be a good fit as a defensive end in this scheme, even if he moved inside to tackle last season.
Moving to the 3-4 will also require some current defensive ends to stand up and move to outside linebacker too. David Gilbert has said he'll be playing some linebacker for the Badgers in this defense, which isn't really surprising. Brendan Kelly would also be a candidate to move to outside linebacker, and both players played standing up a bit near the end of last season in their "Nascar" package. It'll also be interesting to see what the Badgers do with Tyler Dippel and Pat Muldoon in a 3-4, as both players could possibly play outside linebacker too. Either way, some players will have to stay at defensive end, and those decisions will be fascinating.
Can the Badgers run the 3-4 effectively?
This is a pretty big question too. Keep in mind that Wisconsin's current defense was recruited with a 4-3 scheme in mind, so the players might not have the skills necessary to play in the 3-4 at a high level. And specifically on the defensive line, playing in a 3-4 requires a different mindset than playing in a 4-3.
In a 3-4, the defensive line is primarily tasked with stopping the run and eating up space so the linebackers behind them can make plays. The outside linebackers get the sacks and the glory in a 3-4, whereas 4-3 defensive ends are the ones coaches usually count on to make those big plays. It's a change in mindset that shouldn't be overlooked- even some professional players can't handle the mental switch between defensive schemes.
The 3-4 is also a more complicated scheme than the 4-3. Andersen has said he and the coaches will call more zone blitzes and ask defensive linemen (specifically the defensive ends) to drop into coverage from time to time to confuse an opposing offense. It could be that the Badgers take to this new part of their playbook right away, but don't be surprised if there's an adjustment period.
How will the young players fit in?
This is a big spring camp for the defensive line from a schematic sense, but it's also a big one for Wisconsin's young defensive linemen. Andersen hinted on Monday that younger linemen like James Adeyanju and Jesse Hayes will get a lot of reps this spring, which is important for a few reasons.
The biggest is that the Badgers are losing a lot of talent on the defensive line after this season. Allen, Hemer, Kelly, Gilbert, Muldoon, and Dippel are all seniors and won't be back after this season, leaving Hayes and Adeyanju as heirs-apparent on the defensive line, along with Konrad Zagzebski. It's likely that the Badgers will count on them to produce in 2014, so they'll need to use this spring to absorb the new scheme and get as many reps as they can. Reps might be hard to come by in the fall, so they'll need to make the most out of every one they get.
Other young players like Bryce Gilbert and Arthur Goldberg will also need to make the most out of this spring. The Badgers don't have an obvious candidate who could play nose tackle after Allen graduates, so the two tackles will have to use this spring to put on some weight and learn the position if that's the direction the coaching staff wants them to go.
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