2024 IOWA RECAP: Things Can’t Last Forever

A supposedly unsustainable run of tough breaks continues against the Hawkeyes, while an outgoing DC delivers his masterpiece

Photo courtesy Nebraska Athletics.

I just finished my fourth season doing this newsletter.

There are three elements that I think a team can control that overwhelmingly determine who wins a football game, and I’ve tried to track and evaluate all of those elements for Nebraska since the 2021 season. They are:

• Efficiency: How often a team is gaining steady yardage and preventing an opponent from gaining steady yardage. I track this through success rate, a measure of how often a team is gaining or preventing the yardage likely needed to end up converting on a set of downs.

• Explosiveness: How often a team generates big plays or prevents an opponent from generating them. I track this through explosive play rate, which is a team’s total number of designed run plays of 12 yards or more and designed pass plays of 16 yards or more, divided by that team’s total plays.

• Havoc: How often an opponent is creating negative plays against your offense and how often you are creating negative plays against an opponent’s offense. I track this through havoc rate, a measure of a team’s total tackles for loss, sacks, forced fumbles, pass deflections, interceptions, and batted balls, divided by that team’s total plays.

Those are the elements I think you can control. There are a lot of elements that are out of a team’s hands, too: For example, if your efficient plays on offense are spread out over several drives, you may not score as much as you would if they all occurred on two drives. Or if you only give up three explosive plays in a game, that’s a good rate, but maybe all three of those explosive plays went for 75-yard touchdowns. Or if you generate a lot of havoc in a game, there’s no guarantee that havoc will turn into the bounces of the ball you need to generate turnovers. And etc.; there are lots of examples.

But, generally, if a team runs away with all three of those elements I track — efficiency, explosiveness, and havoc — it’s overwhelmingly likely to win by a lot of points on the actual scoreboard. If those elements are close between two teams playing a game, or if the advantages in the elements are split between them, the game on the scoreboard will probably be close. If a team is getting swamped in all three of those elements, it’s probably getting swamped on the scoreboard, too.

In Nebraska’s four games against Iowa since I have started doing this newsletter, Nebraska has won the efficiency battle decisively twice (2021 and 2024), and the teams effectively tied once (2022). Nebraska has won the explosiveness battle three times (2021, 2022, and 2023). And Nebraska has won the havoc battle three times (2021, 2022, and 2024), with the teams effectively tied in 2023. In the four games against Iowa starting in 2021, Nebraska has postgame win percentages — a percentage that uses a game's underlying statistics to estimate how likely a team was to win if it was played 100 times — of 97% in 2021, 99% in 2022, 57% in 2023, and 94% in 2024.

Nebraska is 1-3 in those games.

That should be unbelievable on its face. The natural riposte to that is to bring up Nebraska’s mistakes in these games. That staid, traditional, smart Kirk Ferentz teaches bumbling Nebraska lessons in discipline, no matter what the stats say. And there’s some truth to that: Nebraska has made plenty of memorable gaffes against Iowa, and the Hawkeyes have had a decided special teams advantage over this stretch.

But that analysis doesn’t really hold up in total, either, for a simple reason: Iowa does tons of dumb stuff in these games, too. This year, one of its returners tried to sliding field a kickoff on a meaningless play seconds before halftime for no good reason that was millimeters away from being a safety, and one of its multi-year senior starters in the secondary blew a basic Cover 2 assignment in the final four minutes that would have let Nebraska in field goal range had the receiver not dropped the pass. Last season, Iowa had two kicks blocked, fumbled twice, had its quarterback trip over his own feet on a handoff in the endzone, and threw an interception in the final minute of the game. In 2022, Iowa fumbled four times (two of which led to Nebraska scores), gave up an 87-yard touchdown pass, and had a fourth-down stop wiped out by jumping over the center on a punt-block attempt. In 2021, the Hawkeyes fumbled four more times and dropped a fourth-down touchdown pass in the end zone.

I don’t know how to measure the weight or impact of mistakes on two teams over four games, but all of this is to say these games haven’t really been, “Iowa plays clean while Nebraska screws up a bunch,” as the common narrative would suggest. What these games have really been, though, is “both teams screw up a bunch, but Iowa’s screw ups rarely cost it and Nebraska’s are catastrophic.”

That’s more or less where we are in this series. It’s easy to believe in curses, but curses aren’t real if you’re an adult.¹ When we talk about teams with “devil magic,” we’re usually just talking about teams that do the boring or underlying stuff well that pays off over the course of a game. The aughts St. Louis Cardinals weren’t doing “devil magic;” they were just really good at getting on base and kept games close.

But that’s not what’s happening here with Nebraska and Iowa. Nebraska is outperforming Iowa in these games in those underlying things that matter, while both teams have gaffes. What Nebraska is dealing with here, then, is just a streak of really, really, really poor luck.

The good news is that will balance out in time. Iowa will endure a stretch where they have some heinous breaks in this series, because that’s how math and reality work. That Nebraska is dealing with this now against a team that’s probably NU’s only natural rival in this dead-eyed conference is understandably infuriating. But that it keeps happening against these guys probably isn’t anything more than dumb luck. Teams don’t have curses or hold sway over others; there’s nothing that Iowa’s doing on the field that’s making Nebraska specifically do this:

The moral arc of the universe bends toward justice. If NU continues to outplay Iowa, the wins against them will come. But that was cold comfort over Thanksgiving weekend.

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This week’s sections are:

• Tony White Went Out With His Best Game

• Defensive Adjustments

• A Passing-Game Consolidation

• Rant Of The Week: The Tight Ends Are Going To Revolt Soon

• Unsung Play Of The Week

• Turnover Margin Tracker

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Tony White Went Out With His Best Game

Digging into the underlying data, the Blackshirts’ performance against Iowa was pretty inarguably the unit’s best in the 24 games under Tony White, who left the program the day after the loss to be Florida State’s defensive coordinator. Some people have written off White’s departure, but whatever you feel about his ability to have continued success in the future, he left the program delivering one of Nebraska’s marquee defensive performances of the modern era:

• The NU defense’s 78.6% success rate was the best against any opponent of the last two seasons by a significant margin; the next highest was a 73.7% against Purdue in 2023. Only three other defensive performances in the last two years rose above a 70% success rate: 2023 Iowa (72.7%), 2024 UTEP (72.4%), and 2024 Rutgers (70.6%). All of those other 70%-plus performances were against horrendous offenses; this Iowa unit was top 60 in the country in SP+ offensive efficiency.

• Nebraska’s 31.0% havoc play rate was also the best against any opponent during White’s tenure. Though it did have more total havoc plays (18) in 2023 against Northwestern, that havoc play rate was just 29.5%. NU had 13 havoc plays on Black Friday but only faced 42 total offensive snaps, which inflates that percentage a bit.

• The Blackshirts did not allow Iowa to convert a single third or fourth down in 10 attempts. Nebraska had never had a stop rate on “money downs” higher than 83.3%, when UTEP earlier this season went 1 of 6 in those situations in non-garbage time. The next best performances in those situations had been an 81.8% against Ohio State in 2024 and an 81.3% against 2023 Northwestern. But it had never completely blanked an opponent in those situations before.

• NU tied for its second-best performance on first down of any game in White’s tenure, allowing fewer than 5 yards on 70.6% of its first downs. That tied with the Northern Iowa² game from this year and trailed only an 80.0% rate against Iowa in 2023. The only other game where Nebraska broke 75% on the same metric was against Louisiana Tech in 2023.

• Nebraska’s 3.88 yards per play allowed was tied for the fourth-best mark in any game under White, with the four better games coming against inept offenses. The only rates that were better were 2023 Northern Illinois (2.56 yards per play allowed), 2023 Purdue (3.14), and 2024 Purdue (3.52), and Nebraska’s performance against Iowa was tied with the 2024 Rutgers game. And that’s with the benefit of on 72-yard play that had no real business going for more than 6 yards. If you’ll humor adjusting for that, Nebraska allowed 2.3 yards per play, comfortably the best mark of White’s in Lincoln.

• The success rate on passing downs (second downs of 8 yards or longer or third and fourth downs of 5 yards or longer) of 85.7% against Iowa was the fourth-highest mark of White’s tenure, behind only 2024 Ohio State (100%), 2023 Purdue (90.9%) and 2023 Michigan State (86.36%). Iowa on Black Friday had just two successful plays on their 14 passing down attempts, with one the 72-yard gain on the swing screen on a second-and-13 and the other a 25-yard run on a second-and-8. Meaning that Iowa didn’t have a single successful passing down where the ball was thrown beyond the line of scrimmage.

• The 7.14% explosive play rate allowed was the fifth lowest against any opponent in the last two years. The only games better were against 2024 Northern Iowa (0.0%), 2023 Purdue (3.28%), 2023 Iowa (4.55%), and 2024 Purdue (4.76%). Again, all much worse offenses than Iowa’s profile entering that game or those belonging to an FCS team.

Was this among the biggest wastes of a defensive performance ever? Probably!

Defensive Adjustments

So, how’d White do it?

There were several key tweaks he made to Nebraska’s normal mode of operation to shut down an Iowa team that entered as one of the nation’s best rushing offenses. The Hawkeyes under Kirk Ferentz are the premiere “wide zone” team of college football, meaning they base their offense on outside zone, a perimeter stretch running play with the linemen “elephants on parade” shuffling in an attempt to stress the defense laterally to generate cutback lanes. It looks like this:

If you watch most of Kaleb Johnson’s big runs this year, they’ve come off Wide Zone looks where he runs laterally at first, bursts vertically through a crease, breaks one tackle at the second level, and is gone. Wide Zone is the play you have to stop if you’re facing Iowa. It ran some variation of Wide Zone on 10 of its 42 plays against Nebraska, and it ran several more play-action boots off of the action, too.

The biggest thing White changed to combat it was that he got heavier personnel on the field.

Nebraska’s base defensive personnel under White in the 3-3-5 had been to play with two interior linemen, two edge rushers, two box linebackers, two corners, and three safeties, one of whom functioned as a de-facto nickel. Whatever the proprietary names they have in the building for the positions like JACK or the Rover, that personnel package was Nebraska’s look on 72.3% of its snaps on the season entering the Iowa game.

But against the Hawkeyes, White took the nickel safety off the field for most of the snaps and substituted on a third linebacker:

This personnel — two interior linemen, two edge rushers, three box linebackers, two corners, and two safeties — is, essentially, an old-school 4-3 defense. White more-or-less just decided to switch to an entirely different defensive structure and identity for one game.

Nebraska had used this heavier, three-linebacker personnel grouping some this season in short-yardage situations, on about 8.8% of its snaps, but against Iowa used it on 69.1% of its total plays. The personnel’s previous high usage had been 27.9% against Rutgers, a similar run-heavy team to Iowa with a poor passing attack. But even in the Rutgers game, it still played with the three safeties on the majority of its snaps; what we saw on Black Friday was a wholesale, single-game philosophy change on a level we haven’t previously seen. NU was in the 4-3 on almost every first- and second-down play, then would bring on its base three-safety look or its pass-rush personnel for third downs, but those totaled just 12 snaps. The other 29 plays it faced, it was in the 4-3.

Playing with three linebackers on the field also just increased Nebraska’s presence in the box. NU entered using a “heavy” box — meaning at least one more defender inside the tackle box than the offense can block — on 13% of its plays on average, but it upped that to 31.7% against the Hawkeyes.

The other thing White relied on outside the norm to stop Iowa’s perimeter rushing attack was heavily blitzing the edges.