The in-season overhaul continued Sunday in Lincoln.

Interim coach Mickey Joseph, following a humiliating 49-14 loss to Oklahoma, relieved defensive coordinator Erik Chinander of his duties. Special teams coordinator Bill Busch will take over the unit for the final 8 games.

Nebraska’s defense deserves a lion’s share of the blame for the team’s 1-3 start. And surrendering more than 1,200 yards over your past 2 games will quickly lead to your defensive coordinator getting a pink slip.

But the Huskers problems run much deeper than a porous defense. Turnovers. Poor offensive line play. There’s a long list of fixes on Joseph’s to-do list.

A much-needed bye week has arrived. Joseph promised to look at personnel at all positions. Desperately needing a spark, he might consider a change at quarterback.

Purdy ready for the call

Before we go further, this is in no way an indictment of Casey Thompson and his early-season play.

The Texas transfer has thrown for 995 yards and 5 TDs through 4 games. Leadership and experience are things he brings to the table.

He’s done his work behind a less-than-efficient offensive line. He’s playing dinged up.

But Nebraska needs more. It needs a running threat at QB, and Thompson isn’t it. His 24 carries have gone for minus-19 yards on the season.

Without a true running threat to worry about, Oklahoma’s front 4 pinned their ears back. They recorded 4 sacks of Thompson and several more hurries. He was never able to get comfortable in the pocket.

The defensive blueprint is on film for how to slow the offense.

Thompson left Saturday’s game midway through the third quarter. Florida State transfer Chubba Purdy entered for his first playing time of the season.

The redshirt freshman’s numbers weren’t flashy — 7-of-11 passing for 35 yards, with a pick.

But his 5 rushes for 29 yards were noticeable. Nothing spectacular, but an added dimension for Mark Whipple’s offense.

Purdy found the end zone late on an 8-yard run. He has a burst that Thompson doesn’t. It’s an added element that Nebraska needs moving forward. Especially in the grind of B1G play.

Talented bloodlines

To college football fans, the Purdy name isn’t new. Older brother Brock starred at Iowa State from 2018-21.

Brock Purdy threw for 12,000+ yards and 81 touchdowns and was named All-Big 12 twice during his Cyclones tenure. He was drafted in the 7th round by the San Francisco 49ers.

Father Shawn played baseball at Miami (Fla.) and later in the minor leagues. Athletic genes run in the family.

Rated the No. 6 dual-threat QB out of high school in 247Sports’ composite rankings, Chubba has the tools to put it together.

What he needs is reps. What better time for Joseph and Whipple to test the waters than on a 1-3 team. The pressure’s off. See what the kid can do.

Purdy performed well in spring ball and during fall camp. Whipple said the quarterback competition was close. It was age and experience that gave Thompson the edge. That’s a reasonable factor entering the season. When a team’s lost 3 of its first 4 and has fired its head coach and now its defensive coordinator, the experience factor goes out the window.

With all the issues facing Joseph and his staff, a change at quarterback might provide a spark. If it generates even a small one, it’d be worth it.

Reasonable expectations

Outsiders looking at the Huskers’ struggles will say a change at quarterback is the least of their worries. Defensive changes and addressing the offensive line should come first.

It’s obviously a strong viewpoint.

But Purdy can mask some of Nebraska’s offensive line deficiencies. He has the athleticism to make defenders miss. Extending broken plays is what he can bring to the table.

Obviously a big key to success is revamping the offensive line. Left tackle Teddy Prochaska missed Saturday’s game and is out the remainder of the season with a shoulder injury. Filling in the pieces and finding the right rotation remains a work in progress.

Running back Anthony Grant needs a wingman. A guy who can keep the ball on zone reads to keep a defense honest.

With Purdy’s high upside comes the risk of mistakes. He wasn’t perfect Saturday. His interception was thrown in traffic in the end zone.

His “wow” moments will come with head-scratchers. But at this point the risk is one worth taking.

What are the remaining expectations for Nebraska? Six wins and a bowl berth? Seems unlikely.

Nebraska needs to use the bye week to start from scratch. Repress the brutal memories of Games 1-4. Start anew.

With all the tasks at hand for Joseph and staff, why not give Purdy his shot?

At this point, what do they have to lose?