IOWA CITY — For years, Iowa didn’t have much to worry about at linebacker.

The Hawkeyes head into spring workouts with question marks at all three spots after losing a veteran trio keyed by All-American Josey Jewell.

Iowa (8-5 in 2017) knew for the past few seasons that Jewell, Ben Niemann and Bo Bower, who combined for 122 starts, would anchor a defense that routinely finished among the best in the Big Ten. But such a luxury always came with the downside: Iowa would eventually need to break in three new starters at the same time at a position where experience, communication and leadership are crucial.

The Hawkeyes didn’t find much clarity during bowl preparation in December, so working toward building a unit that can be ready to go by September will be perhaps Iowa’s biggest challenge in spring workouts.

“It’s anybody’s ballgame right now,” Iowa coach Kirk Ferentz said.

The Hawkeyes will open the spring with Nick Niemann, Ben’s little brother, at outside linebacker, junior Kristian Welch in the middle and senior Aaron Mends on the outside.

But being listed as a starter on the depth chart in March might not mean a lot — if anything — in August. Senior Jack Hockaday and Amani Jones also figure to crack a rotation full of guys heavy on special teams experience but light on snaps at their listed position.

Barrington Wade, a redshirt sophomore who has yet to take the field for Iowa, is listed as Niemann’s backup. Freshman Dijmon Colbert has moved from defensive back to linebacker to bolster Iowa’s depth, and there’s a possibility that safety Jake Gervase might move to linebacker could happen in the fall.

“Some guys have a lot of position flexibility, other guys maybe not as much. So the key for us right now is, I think, figure out who the best three (linebackers) are and where can we put them most effectively. And then, if we can find a fourth guy, a fifth guy, a sixth guy, just kind of take it a day at a time.”

Iowa’s formula for success under Ferentz, now in his 20th season, has been to lean on a bend but don’t break defense and a punishing running game that controls the tempo and limits turnovers.

But the Hawkeyes don’t know who’ll be their starting running back either.

Iowa lost a pair of seniors in Akrum Wadley and James Butler and will look to replace them with a thin group of largely untested youngsters.

Sophomore Toren Young, who’s listed at 5-foot-11 and 221 pounds, is listed as a starter. The Hawkeyes also return sophomore Ivory Kelly-Martin, who averaged 21.3 yards on 21 kickoff returns and ran for 184 yards in limited duty.

Toks Akrinbade is among a group of players being held out of spring practice for undisclosed medical reasons, and redshirt freshman Cam Harrell will work out at running back this spring after working with the defensive backs in the fall.

“We like our running backs. But there’s just not that many of them,” Ferentz said.