How is Iowa football's defensive line progressing this summer? Jay Niemann provided an update.

Iowa assistant defensive line coach Jay Niemann understands the looming expectations of his room this upcoming season.

The Hawkeyes return eight of their top nine contributors from last year, equating to more than 75% of its production (total tackles, tackles for loss and sacks) returning.

A trio of seniors headline the group in Joe Evans, Noah Shannon and John Waggoner. Junior Logan Lee has earned preseason All-Big Ten honors and sophomore Lukas Van Ness, the team's leading sack getter last season, has perhaps the highest ceiling and a new position, switching to defensive end full-time this year. 

On paper, there's plenty to be excited about and returning experience points to a breakout year for the group. But Niemann is tempering those expectations. 

"There's plenty of room for improvement," Niemann said. "You're never a finished products. And if you listen to some of the guys, even at the NFL level talk, guys that have eight, nine, ten years of experience, they're always trying to master their craft. They're always trying to find something to get better at always trying to find a way to improve their game. 

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"We've got three seniors in Noah, John Waggoner, Joe Evans and they're leading the charge but I think all three of them will tell you that there's three or four things about the fundamental and technique aspect of their game they'd like to get better at." 

Iowa's defensive line has four All-Big Ten preseason selections: Joe Evans, Logan Lee, Noah Shannon and Lukas Van Ness.

Summer conditioning allows for just that. In addition to strength and conditioning work, players go through eight hours per week for on-field activities. Coaches are allowed to go through positional drills with players, but helmets, pads and any 11-on-11 work are prohibited. Those limitations narrow the scope down to sharpening those basic skills. 

Past that, players are allowed to watch film on their own. Niemann and defensive line coach Kelvin Bell know they can count on several players physically but the mental aspect of the game is where they want their players to progress the most. 

"I talk to the guys all the time about developing and increasing their pre-snap intelligence," Bell said during spring practice. "That's not just turning around, getting the call from (defensive coordinator Phil Parker) and putting your hand in the dirt and playing. There's millions of (offensive) cues that young guys that haven't played a lot of reps, they're just not looking at that.

"They just may be thinking 'I got the call, let me line up in the right place.' So I think as a group as that increases, I think the production of the group increases because what you get is guys that are able to play above and beyond what the play call is." 

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Iowa's defensive line group returns eight of their top nine contributors in 2022.

Niemann acknowledged that the bulk of that will come in season when they're actually put in real situations but the film study taking place now is critical. Winning pre-snap is process of elimination, the faster a defender can whittle down the possibilities of what can and can't happen out of a formation, the better. 

Many returning players this year were first-time, major contributors last season. Now, they can use that experience to watch for more subtle aspects of offensive sets outside of the personnel grouping. According to Niemann, those nuances include things like depth of running backs in the backfield, if tight ends are set on or off the line of scrimmage and if off, where they are specifically. 

"There's a myriad of things," Niemann said. "It depends formation by formation and personnel group by personnel group what exactly it is we're trying to glean from those little bits of information that we can pass along to our guys. More importantly, it's not that we know it, but they have to know. It doesn't matter what we know it matters what they can do." 

Iowa defensive lineman Lukas Van Ness (91) is among the defensive lineman on the 2022 team that's primed for a breakout season.

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The challenge at this part of year is not only preparing known contributors but developing younger players. And there's a lot of them in the room. Of the 20 defensive linemen on the roster, 13 of them have sophomore eligibility or younger. 

The coaches have different methods of keeping them engaged such as meeting room tests and quizzes, playbooks on iPads and more written notes to study in their free time. 

"You sure wouldn't expect a true freshman to have the same knowledge base as a junior or senior," Niemann said. "But you're trying to bring them along as far and as fast as you can, so that they can close that gap as rapidly as possible so they're as ready to play as they can be." 

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Health pending, Iowa's defensive line should be one of the deepest and most productive position groups on this year's team. Aligning high expectations and production won't be easy, Niemann said, but what's working in their favor is that with more established leaders than a season ago, the group is taking the right approach in working on their development. 

"They're doing the right kinds of things to to get better," Niemann said. "And after coaching a number of places I can tell you it's not this way everywhere. So I've really liked it the guys in our room, the cohesiveness, the chemistry that we've got going and appreciate the way they go about their business every day." 

Kennington Lloyd Smith III covers Iowa Hawkeyes football and men's basketball for the Des Moines Register. You can connect with Kennington on Twitter @SkinnyKenny_ or email him at ksmith@gannett.com.