There isn’t a Pac-12 defense that will need to replace more major contributors than Washington.

The entire defensive front of Danny Shelton, Hau'oli Kikaha, Andrew Hudson and Evan Hudson is gone. So are Paul Hornung Award winner Shaq Thompson and John Timu, who led the Huskies in tackles during two of the four seasons he started. Washington assistant coach/linebackers coach Bob Gregory has his work cut out.

“Well, that’s college football,” Gregory said. “It’s never approached that there’s a problem. It’s just, ‘Hey, we’re moving on, that’s just the way it is.’ You’ve got pro football where you might have guys for a long time but [here] you’re going to graduate guys every single year.”

But they’re not just replacing “guys.” They’re replacing their front four, and more specifically for Gregory they’re replacing two of the best inside linebackers that Washington has seen in a while.

Thus far the eventual heirs to the thrones look like the 2014 backups -- Keishawn Bierria for Thompson and Scott Lawyer or maybe Azeem Victor for Timu.

Bierria started four games in 2014, including picking up starts during the two games that Thompson moved over to tailback. Gregory said Bierria could be joined in the competition by outside linebackers Travis Feeney and Cory Littleton as the Huskies search for that perfect match of productivity and playmaking ability, but in Bierria’s limited time this season Gregory was impressed with his natural instinct and how he “made plays when we needed to make some plays.”

“He’s got a chance to be a good football player,” Gregory said. “Hopefully sooner rather than later."

Gregory is also hoping that Lawyer or Victor proves himself as a starter sooner rather than later. Lawyer has the upper hand when it comes to experience, Gregory noted, but he also said he sees great potential in Victor, who redshirted last season.

But the common thread to all of these guys is this: Everyone is going to be relatively inexperienced and everyone is going to be replacing someone who was far from that.

Which brings up the topic that Gregory will have to bridge this season -- balancing the expectations of the players who fill these shoes in the fact that maybe they don’t need to be filled in the exact same way as the player who came before them.

There seems to be an art in this transition and Washington won’t be the only Pac-12 team that has to face this issue. Gary Andersen and Mark Helfrich both need to replace recording-breaking quarterbacks. Kyle Whittingham needs to replace the conference leader in sacks. Steve Sarkisian needs to replace a 100-yard-per-game rusher. And all of the conference players who step into these roles will be younger, less-experienced players.

Does Gregory expect Bierria to score four defensive touchdowns next season? Does Gregory expect Lawyer or Victor to come in and register a 100-plus tackles in his first year starting?

No. But Gregory has seen it done at each of those positions so he knows that it is possible.

“These kids are competitors and they have very high expectations,” Gregory said. “But, it’s all about them, it’s all about you as a player developing. We don’t want them to think they need to be Shaq, we just want whoever it is to be themselves and to develop and be consistent players and play hard -- but all within themselves.”

Interior expectations aren’t the only thing Gregory needs to balance. He knows that in year two of the Chris Petersen tenure, there will be higher expectations from the administration and the public and within the coaches themselves -- all of this after losing so much on defense.

“It’s another year, the expectations are going to be a little bit higher,” Gregory said. “On the flipside, we’re going to have a lot of new faces on the defense. … We want to push the players as much as we can, but we have to bring those players along at a good pace and slowly so they can get it.”

Luckily for Gregory, all of these guys are on campus right now -- Washington isn’t relying on any true freshmen who won’t get to campus until June or July. And what each of these players is missing -- experience -- is only going to be found on the field.

Washington kicks off spring football on March 30.

“Now the challenge is the next guy up and we’ve got to develop those kids and bring them along at a fast pace,” Gregory said. “You go through winter conditioning and you hope you get better; you go through spring football and you hope you get better; then it’s summer. You hope all these phases of the offseason you want those guys to continue to improve.”