Walking into one of Nebraska’s spring practice this year probably feels a lot like a real-life game of “Guess Who.” Especially if you looked at the offense.

Mike Riley has had to answer questions about his offense in the past. Mostly, though, those were focused on general scheming, incorporating a more effective rushing attack, or improving Tommy Armstrong, Jr.’s accuracy. Personnel hasn’t been a topic of conversation he had to handle in his first two years.

That’s not the case this time.

Nearly 80 percent of the Huskers’ offensive production from last season has departed. In addition to losing Armstrong – its mainstay at quarterback – Nebraska is also losing leading receiver Jordan Westerkamp and top rusher Terrell Newby. Also gone are Brandon Reilly and Alonzo Moore, who ranked third and fourth on the team respectively in receiving yards last season.

Essentially, Riley and offensive coordinator Danny Langsdorf are getting a clean slate in 2017. But that fresh start isn’t going to translate into a new offensive mindset.

“I think you’ll see a few different things,” Langsdorf told Land of 10‘s Chris Heady. “But I don’t think you’ll see this drastic shift in offensive philosophy.”

The quarterback’s role is going to be one of those few differences.

Oct 17, 2015; Minneapolis, MN, USA; Nebraska Cornhuskers wide receiver De'Mornay Pierson-El (15) celebrates with teammates after scoring a touchdown in the second half against the Minnesota Golden Gophers at TCF Bank Stadium. The Cornhuskers won 48-25. Mandatory Credit: Jesse Johnson-USA TODAY Sports

With Armstrong out of the picture, the starting quarterback job is going to be a battle between Patrick O’Brien and Tulsa-transfer Tanner Lee. Both have received high praise in early spring, but both are also pocket passers. Regardless of who wins the race, it’s going to be the first time Nebraska hasn’t had a dual-threat quarterback under center since the pre-Taylor Martinez era.

Both Langsdorf and Riley have hinted at a significant decrease in the number of designed quarterback run calls because O’Brien and Lee don’t possess that same mobility Armstrong showcased.

O’Brien and Lee aren’t going to be as effective as scramblers outside the pocket, either, meaning Nebraska’s receivers are probably going to be even more important than they were a season ago.

Stanley Morgan, Jr. and De’Mornay Pierson-El are the team’s key returners from last season, combining to catch 53 passes for 707 yards and three touchdowns. While they’ll both likely be the top two options in the passing attack, the Huskers are going to need more.

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That probably means throwing some young guys into the mix early. The early enrollment of four-star receiver Jaevon McQuitty and three-star Keyshawn Johnson, Jr. is certainly a bonus for Riley. Joining those two in the fall will be another four-star prospect, Tyjon Lindsey. All three could see immediate playing time.

For Nebraska, quarterback and receiver are the two positions that are the biggest unknown. And while there should be a heavy emphasis on developing talent there, Riley doesn’t want to lose site of what the offense really needs to be doing.

“We’re still going to be a 50-50 team, because I know better than that,” he told the Omaha World-Hearld. “It is very difficult to drop-back pass protect for a drop-back style quarterback and do that 40 times a game.”

The Huskers were able to establish a strong rushing attack early in the season that eventually floundered late in the year. By the end of Riley’s second campaign, his team averaged 169. 2 yards per game on the ground, ranking ninth in the B1G.

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In an interview after a spring practice, Riley mentioned that he wanted his team to “run it better.”

Again, with the top two rushers gone – one of which was Armstrong – that’s going to be a challenge.

Devine Ozigbo and Tre Bryant are going to be the candidates battling it out for touches this spring through the fall. If Mikale Wilbon could become a little more consistent, he might work his way into the rotation, too. But none of the three have been a featured back for any length of time.

Ozigbo was the team’s third-leading rusher last season, tallying 412 yards and five touchdowns on 97 carries. Bryant toted the ball for 172 yards and a score and Wilbon fell short of reaching the century mark.

Oct 22, 2016; Lincoln, NE, USA; Nebraska Cornhuskers head coach Mike Riley leaves the field after defeating the Purdue Boilermakers at Memorial Stadium. Nebraska won 27-14. Mandatory Credit: Bruce Thorson-USA TODAY Sports

Without a proven ball-carrier and losing the rushing threat at quarterback, Nebraska improving its rushing attack in 2017 doesn’t seem like a feasible task. But Riley has some ideas.

Riley would like to see a few more screen passes worked into the playbook, something he believes can open things up offensively. He referenced his Oregon State days in an article with Omaha World-Hearld, saying “We were so good at the screen, it really is (like a run game). We had a lot of big plays on that.

“You see every blitz in the world, every stunt in the world. But if you’re balanced, the draw and the screen and running the ball levels everything off.”

Whether or not losing the dual-threat weapon at quarterback or the high player turnover sparked these tweaks isn’t certain, but implementing some changes comes at a good time. With two years under his belt, Riley has had time to gauge what does and does not work in the B1G.

Riley and Langsdorf appear to be moving the offense in the right direction. They’re not forcing an offense designed for Armstrong, Newby, Westerkamp and company on the new suitors at those positions. That’s a good thing.

In order to execute effectively, though, Nebraska has to develop some playmakers.

Who will step up?

That’s the question Nebraska is going to have to have answered by the time the season kicks off.