LINCOLN, Neb. -- Enough with the nice-guy label.

Last week after signing day, Bob Diaco, the former UConn coach hired in January to restructure the defense at Nebraska, shared his first impressions of Mike Riley, the Cornhuskers’ coach set to enter his third season in 2017.

“A super nice guy, a fun guy,” Diaco said.

Mike Riley, "energized" by some new faces and new ideas on his coaching staff, is eager for 2017. John S. Peterson/Icon Sportswire

That is every person’s first impression of Riley -- recruits, their parents, fans, fellow coaches, the media, parking cops, student workers in the offices around him. Truth is, Riley doesn’t love the label. Of course, he probably won’t mention that. And if he did, he’d wear a smile to help rid the moment of tension.

Riley’s unassuming front sits at the heart of his persona as a nice guy. But it’s an image from which the 63-year-old coach has made strides this offseason to break free, possibly representing Nebraska’s best chance to snap a conference-title drought that spans 17 seasons.

After his four decades in coaching, the time is here to look beyond Riley’s exterior. Behind it, lurking, is a calculating and competitive nature. Two years into the closing chapter of his career, Riley has served notice that he’s prepared to step out of character, if required, to clear an imposing set of hurdles.

Can an edgier Riley, open to change, create a contender out of Nebraska?

Maybe. Maybe not. But he appears determined to find out.

He corralled Diaco to replace Mark Banker, alongside whom Riley coached for 20 seasons at four stops. With Diaco at large and coveted by others, Riley fired Banker by phone as the former coordinator traveled during the height of recruiting season.

Then Nebraska signed up to pay $1.7 million to Diaco over two years, by a large margin the most lucrative contract ever given to an assistant at the school.

Riley also deposed special-teams coordinator Bruce Read. They had spent 15 seasons together. Secondary coach Brian Stewart left on his own, and Riley has reportedly settled on former Notre Dame assistant Bob Elliott to coach the secondary with newcomer Donte Williams, formerly of Arizona.

“By no means were those easy decisions,” said another longtime Riley confidante, Dan Van De Riet, Nebraska’s associate AD for football operations. “To say that he didn’t struggle with those would render him almost lifeless.

“But for whatever reason, I’ve seen a growth in energy. I’ve seen him more motivated and more engaged than ever. He’s more aware of the direction that he wants to take this program.”

The Huskers improved from 6-7 in Riley’s first year to 9-4 in 2016. Still, a sour taste persists, because Nebraska limped to the finish after a 7-0 start. Ugly defeats at Ohio State and Iowa marred a season that otherwise featured reason for optimism.

“I’m always interested in change,” Riley said. “I don’t like to go through it necessarily. The process is hard, but you have to be fair to the whole university and the whole program. You’ve got to put yourself through that process -- and personally, be very blunt about it, what we need to do.

“I’m energized and excited by our team and want to push in any way to be better.”

In terms of personnel and scheme, Riley has effectively hit the reset button in 2017.

Diaco plans to install his 3-4 scheme this spring, perhaps an attempt by Riley to mirror the strategy that Big Ten West pacesetter Wisconsin has used to its advantage. We’ll soon see if the active and agile linebackers so essential to the Badgers’ success reside on the Nebraska roster.

Coordinator Danny Langsdorf loses a four-year starter in Tommy Armstrong Jr. but finally gets to tailor his offense around a quarterback well-suited to run the system he prefers. Transfer Tanner Lee enters this spring with a slight edge over redshirt freshman Patrick O’Brien and early enrollee Tristan Gebbia.

All of it amounts to a gamble. But that’s what Nebraska invited with Riley, an unconventional choice for this job despite his decades of experience and a personality that fit with the ideals of the Nebraska program.

Now, two years in, Riley’s vision for the Huskers has grown sharper. His focus has narrowed.

“Absolutely, Riley said, “I’ve got a better idea of what we need to do.”

Van De Riet insists that Riley “has not changed one bit.” This side of him that embraces change has long existed.

“Maybe he doesn’t trigger the same things you see from a lot of other coaches or leaders who are known as competitive types,” Van De Riet said. “But you can’t just assume that because he’s a nice guy and has a great culture in his locker room that he can’t be competitive.”

Indirectly, Riley is intent to change the narrative around himself and Nebraska. Winning big would do it.

“He’s a head coach who has been through it all,” Diaco said. “His way of doing things is just very fine-tuned by a master. It’s impressive, and that’s why I’m here, for sure. I had other options. I came because I believe in him.”