Musings from Arledge: The disconnect in D'Anton Lynn's 2025 USC defense

So USC and Penn State appear to be in a game of chicken as USC waits to see whether Penn State will pay for D’Anton Lynn’s buyout. 

I say a cut a deal with Penn State and let him go.

Here are three statements, all of which are true:

D’Anton Lynn has been a major upgrade from Alex Grinch.

D’Anton Lynn is likely to have a very long, very successful coaching career.

D’Anton Lynn’s performance this past season was extremely disappointing and, frankly, unacceptable.

Lynn took over from arguably the worst defensive coordinator in USC history. I know there’s competition from Helton’s tenure and from an obviously past-his-prime Monte Kiffin. But I still think we can award the title to Alex Grinch, whose units weren’t just bad, they were comically inept. 

Grinch had a tendency to make the worst possible schematic choices at the worst possible time. 

He was, for example, a big fan of Cover 0 (man coverage with no deep help) when not blitzing and while knowing that his front four didn’t have a pass rusher. The downside to this defensive call is that you have a safety on a quick slot with no help and he has to cover him for a very long time. The upside is … well, I’m not sure there was one. Man has yet to invent a defense more likely to give up a big pass play. Grinch went back to that well over and over. It cost USC the Cotton Bowl and a lot more.

Grinch also frequently gave up big run plays based solely on alignment, and would repeat that process over and over. Against Washington he never once adjusted to the toss sweep, which the Huskies ran over and over. He continued to insist that a secondary guy a few yards off the ball would set the edge. He never did.

Lincoln Riley’s biggest mistake was bringing Grinch from Norman and then keeping him an extra year. It was a huge mistake. With Grinch around, Caleb Williams was required to score a touchdown on every single possession because it was clear the defense would never, ever, get a stop. Grinch set the Guiness Book record for most losses while scoring more than 40 points.

We all cheered when D’Anton Lynn replaced Alex Grinch. And rightfully so. I would have taken anybody at that point. I probably would have cheered had Clay Helton returned as defensive coordinator to replace Alex Grinch, such was the desperation of the times.

And the early returns were promising. USC was small and unathletic on the front seven in 2024 with the exception of Bear “It’s My Party and I’ll Quit If I Want To” Alexander. The defense often wore down as the game went on. But that 2024 unit played hard and played fundamentally sound. And Lynn and Doug Belk showed the ability to develop secondary talent; Jaylin Smith went from arguably USC’s worst starting defensive player in 2023 to a stud in 2024. Smith gets credit for that, but so does D’Anton Lynn.

But something strange happened before the 2025 season. USC massively upgraded its size and talent upfront—and the USC coaches talked a great deal about how the defensive line was going to be dramatically different in 2025—but the performance on the field was bad. Genuinely bad. USC could not rush the passer against any halfway decent team, and USC had one of the worst run defenses in the nation based on success rate. That combination was not on my Bingo card preseason. And it clearly wasn’t on D’Anton Lynn’s or Lincoln Riley’s either, which raises the terrifying possibility that these guys just had no ability to judge the talent in their own defensive line room. 

I get that USC is still in the process of upgrading its talent. I understand they don’t have Ohio State’s players defensively. I don’t get how competent coaches could be convinced they have a very good defensive line room and then turn in the performance we saw this past year.

This is the point at which USC fans try to redirect and pretend that the coaches didn’t play up the defensive-line talent, where we pretend that USC just wasn’t big enough to be successful. But that’s all nonsense. The coaches did talk up the talent level in the defensive line room. Here are just a few examples:

Lincoln Riley: “The second part of it is that talent is continuing to rise, especially on the defensive front. We all know, obviously, how important that is and this defensive front this year is just — frankly, it’s going to look a lot different. There’s more talent, there is more depth. It is trending in a way that’s very exciting to everybody that follows the Trojans.”

More Lincoln: “I think this group certainly has a chance to get back to that dominant play…”

And check out the 10:18 mark from this interview, as Riley lavishes praise on his defensive line group.

And the coaches heaped praise on certain individuals, including the now portal-bound Devan Thompkins. This is just one example from Eric Henderson.

The USC coaching staff loved the defensive line room. 

And there was plenty of size in that room. Many of the best interior linemen in NFL and college history were in the 290-pound range, including John Randle, Warren Sapp, and Aaron Donald—or from USC lore, Mike Patterson. Elite edge rushers often play around 250 pounds in the NFL.

USC had enough size. It had a group that the USC coaches thought would be very good. And that group had no ability to rush the passer and was one of the worst teams in the country in rush defense success rate. How do we explain that?

The USC coaches pulled highly regarded Keeshawn Silver out of the transfer portal, believing he could control an A gap. He couldn’t. They talked up Devan Thompkins, believing he would be a star. He wasn’t. Both guys were below-average Big Ten interior defensive lineman. How do we explain that?

Any attempt to come to terms with the 2025 season and D’Anton Lynn’s future at USC must take into account that USC had a whole group of highly regarded, highly compensated coaches who were, apparently, completely surprised that their defensive line just wasn’t any good.

Part of that problem was an inability to motivate the players. USC consistently played without passion in the first half of games. Getting players to play hard—and sitting guys that won’t—is a big part of a college coach’s job.

Another big part of the failure was coaching the fundamentals. USC’s front seven played fundamentally unsound. The problems were glaring and never got addressed.

This is a clip touting one of the Illinois offensive linemen. A cruel friend sent this to me the other day. I include it here not because it is an aberration but because it is not. 

JC Davis brings 50+ starts at LT and is coming off a First Team All-Big 10 selection.

Once an unranked recruit, Davis has worked his way up, starting at:

Contra Costa College ➡️ New Mexico ➡️ Illinois. https://t.co/B29EaBwwjY pic.twitter.com/5uiNwUeYdD

— Logan Armstrong (@loganarm10) December 16, 2025

USC had three major problems in the run game. First, the interior guys played much too high and frequently got driven into the defensive backfield. That’s a technique problem, especially when you’re talking about guys who are between 290 and 330 pounds. 

The other two problems are demonstrated in this clip. The edges consistently came too far upfield to set the edge. What, exactly, is the edge doing in this clip? This is a four-start recruit in his third year in the program and he has no idea what he’s doing. This looks like a Pop Warner play, and it happened over and over again.

And the linebackers were simply unable to make basic run reads and fill a gap. Stephans and Gentry are both standing still yards from the line of scrimmage as two enormous holes open in front of them and do they nothing.

A fundamentally sound defense has Shelby meeting the H back about a yard upfield with his shoulders square and squeezing the edge, and a sound defense has Gentry and Stephans filling their gaps. USC does none of those things. And this was a constant occurrence, play after play, game after game. I complained about it game after game. I could show you dozens of clips just like this. Against Notre Dame, it happened on virtually every down.

And Lynn’s response was to tell the media nonsense. He and Riley said that the defensive line took too long to get going against Illinois. No, they didn’t. They never got going. And the problem we see in that X clip is one of basic technique. When guys don’t set the edge, it’s not a problem with getting going. It is a fundamental problem with technique. 

Lynn also said repeatedly that Desman Stephans is getting better and doesn’t make the same mistake twice. But he does, I assure you. He made the same mistake almost every run play for the entire season. He would wait and wait, unsure how to respond, until an offensive lineman got to the second level and smashed him. Occasionally, Lynn would call for a run blitz so Stephans didn’t have to think, and that would often work. But the poor guy could not read a run play. He couldn’t, and he didn’t, and it never got fixed. Rob Ryan said in the offseason that USC’s linebackers would play downhill and splatter people. Is that what we saw?

So where does that leave us? If USC brings back D’Anton Lynn and the rest of the defensive staff, we have to wonder what exactly will change this coming year. Will the fundamentals get cleaned up? Will the defense play hard in the first half or be content to get pushed around for a half week after week? Will the USC coaches now understand the talent level of their own players, or will they continue to overrate them dramatically? Will the USC coaches be able to discern which guys in the portal can play, or will they land a new crop of Keeshawn Silvers and DJ Harveys?

The truth is that USC spent a fortune of defensive coaches with good reputations, guys that I expect will have long and successful careers. But other than the secondary coaches who got dealt a bad injury hand and showed an ability to develop guys over the last two years, the current defensive staff appeared to be overrated and performed poorly. If Lynn comes back, I’ll support him and hope for the best. But after watching the 2025 season, there is no reason to keep him away from Penn State. Maybe D’Anton Lynn is an NFL coach. Maybe his strength is scheming against NFL offenses with players who are already professionals and already know the fundamentals. Maybe teaching young guys how to do the basics just isn’t his primary skill set. I’m not sure.

But there are available replacements with better track records. Sark needed a scapegoat to justify a disappointing season at Texas this year, and Pete Kwiatkowski fit the bill. But Kwiatkowski was a Broyles Award finalist a year ago when Texas had the best defense in the SEC, and he was a Broyles Award semifinalist the year before that. Throughout many years at Boise State and Washington, Kwiatkowski’s defenses were consistently good. Sark needed an excuse, but there is no reason to believe that Kwiatkowski forgot how to coach after two decades of success. 

So maybe it’s just time for USC to move on. I don’t know if Kwiatkowski would take the job or if he’d succeed as he has in the past. But I do know from recent experience, maybe the worst thing you can do is hold onto a defensive coordinator who isn’t working out. And after this past season, there is reason to believe D’Anton Lynn is not working out.