Is Iowa football's defensive line poised to make a big leap? Returning experience says so.

There's a much different feeling in Iowa's defensive line room this year compared to last year.

In 2021, the unit lost three future NFL players: Chauncey Golston (Cowboys), Jack Heflin (Packers) and Daviyon Nixon (Panthers), and questions about who would replace them were among the biggest storylines of last off-season.

This spring, there's much more certainty and confidence among the group. 

"I feel like the room is definitely a lot louder," veteran defensive tackle Noah Shannon said. "When (defensive line coach Kelvin Bell) is talking, asking questions, there's more guys who are confident to speak now."

Shannon said that because so many players got significant playing time last year, they know more because they've seen a lot more. Bell later chimed in that many players didn't speak up last year because senior Zach VanValkenburg typically had the answer for everything. 

VanValkenburg is gone and preparing for the NFL Draft, but the Hawkeyes return plenty of experience and talent in 2022. VanValkenburg is the lone departure, meaning Iowa is returning more than 75% of its production (total tackles, tackles for loss and sacks) from last season. 

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Iowa is returning eight of its top nine contributors last year. The group has gotten off to a strong start this spring and could take one of the biggest leaps of any Hawkeye position group. 

And the Hawkeyes aren't done adding talent to their defensive line. Aaron Graves, a four-star recruit and Army All-American, will join the team in June. Iowa already has two early enrollees participating in spring practice: three-stars Brian Allen and Caden Crawford. 

"There's a lot of guys who've played for us that are returning," Bell said. "That changes the dynamic of the room. The amount of guys that we have and the reps they're getting is invaluable. Got a couple of guys who have enrolled early, which is the first time for me. I couldn't be more pleased with where we are, which a lot of it is due to a lack of injury; knock on wood." 

The leaders who have emerged include seniors Joe Evans and John Waggoner at defensive end and senior Noah Shannon and junior Logan Lee at defensive tackle. 

Shannon said he, Evans and Waggoner had conversations during the winter period about taking over the leadership void left by VanValkenburg. Their message to the younger guys in the room is that they can feel comfortable speaking up despite their age.

"No one person is bigger than the other," Shannon said. "We want the young guys to be able to approach us and coach us too. If I'm out there messing up then I want the younger guy to be able to say 'Hey, you're not doing this right.'"  

On the field, there's opportunity available for almost every player to get significant reps. Evans has been out with an injury and sophomore Ethan Hurkett is still recovering from a leg injury that sidelined him for most of last season. Those injuries have opened the door for more snaps for the defensive ends. Sophomore Deontae Craig has gotten a lot of first-team snaps in Evans' place and fellow sophomore Lukas Van Ness, last season's co-sacks leader, is experimenting at defensive end after playing mostly tackle last season. 

Logan Jones' move to the offensive line opened up an opportunity for reps at defensive tackle. Bell said junior Louie Stec and redshirt freshman Jeremiah Pittman are two players who are taking advantage. 

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"A lot of guys are getting more reps than they probably thought (they would) this spring," Shannon said. "I think it's good for them, and their sense of urgency to improve is very high. We have our scheduled meetings but a lot of guys are getting extra sessions in with (assistant defensive line coach Jay Niemann) and coach Bell, and you can see it on the field every day. They're not going to mess up on the same thing every day." 

Iowa junior defensive lineman Noah Shannon forces Indiana junior quarterback Michael Penix, Jr., to get rid of the ball in a hurry in the second quarter of the game at Kinnick Stadium in Iowa City on Saturday, Sept. 4, 2021.

With several proven commodities, Bell is emphasizing the mental aspect of the game as the next step in the group's development. Bell foresees more disruptive plays from the group once they can better identify what the offense is doing pre-snap. 

"I talk to the guys all the time about developing and increasing their pre-snap intelligence," Bell said. "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 from where the offensive tackle is looking, location of the fullbacks and tight ends that young guys that haven't played a lot of reps, they're just not looking at that. 

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"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." 

The defensive line's continued emergence should solidify Iowa as a top defensive team in the Big Ten again in 2022. Last year, with a largely inexperienced defensive line, the Hawkeyes finished first in takeaways, third in total defense, third in rush defense and sixth in pass defense. More consistent (and disruptive) defensive line play will make life much easier for Iowa's back seven, which is also expected to perform at a high level. 

For Bell, it's too early to put energy into season projections. What he does know is he has a core group that he can trust and hopes more players earn that trust between spring and fall to fulfill the expectations. 

"There's guys I know I can count on based on what they did last year," Bell said. "Then there's guys I'm waiting to emerge and see if I can count on. There's some guys you feel good about, guys you keep your fingers crossed that you hope do well and everything they're doing right now would lead you to believe they'll have a good fall but it hasn't happened yet." 

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.