Iowa’s defensive line was a model of consistency last season.

Right end Zach VanValkenburg, defensive tackle Daviyon Nixon and left end Chauncey Golston started all eight games. Jack Heflin started seven of the eight games at defensive tackle, with Noah Shannon getting the other start.

But Nixon, Golston and Heflin are gone. Which means there is still uncertainty on the starters on the line heading into next week’s opener against Indiana.

The questions that Iowa has on its offensive line are mirrored on the other side of the ball.

“Both of our lines right now, we have some really good players up front on both sides, but we also have a bunch of guys that haven't played much,” coach Kirk Ferentz said.

The Hawkeyes have been successful in the past with a rotation of defensive linemen, and it’s likely that happens again this season because of all of the questions.

VanValkenburg is the constant, with plenty of experience. He’s heading into his sixth season after an impressive 2020 season in which he tied for the national lead with four recovered fumbles. VanValkenburg was a second-team All-Big Ten pick by the coaches and the media after a season that included 30 tackles, 8 ½ tackles for loss and 3 ½ sacks.

John Waggoner is No. 1 on the depth chart at left end, but Joe Evans will see plenty of time there as well.

Waggoner played in four games last year and 10 games in 2019. Evans joined the Hawkeyes as a walk-on in 2018, eventually getting a scholarship last season. He has 14 tackles in his career, including six for loss and five sacks.

“Joe has just been going hard ever since he got here,” Ferentz said. “He just has such a high motor. And then the question was is he going to be big enough to do some things and all that. But I remember out here, I'm thinking of the Minnesota game in '19 (when Evans had three tackles) he helped give us a little juice out there. And he's just one of those guys … he just goes hard. Everything he does is first class. So he just continues to keep getting better and better.”

Yahya Black, No. 1 on the depth chart at right tackle, might be the most intriguing player on the line. Black, at 6-foot-5 and 287 pounds, played in four games last season as a true freshman, with one solo tackle and two assists. Black missed the first three games of the season because of injury, but played four of the last five.

Shannon, listed No. 1 at left tackle, has played in 15 games in the last two seasons. He had 11 tackles, including a half-sack, last season, after five tackles as a redshirt freshman.

There isn’t a lot of experience among the No. 2s on the depth chart. Left tackle Lukas Van Ness is a redshirt freshman who has yet to play a game. Sophomore Logan Lee, at right tackle, played in two games last season, with one tackle. Redshirt freshman Deontae Craig, behind VanValkenburg, also did not play last season.