SOUTH BEND, Ind. (AP) — Notre Dame's defense seems to have turned a corner.

Four games into last season, it was answering question about whether it was stout enough to help the Fighting Irish make a title run. Four games into this season, the numbers indicate there's not much doubt.

The third-ranked Fighting Irish (4-0) allow the fewest yards per game and second-fewest points per game in the Football Bowl Subdivision heading into Saturday's game at North Carolina.

“They’re executing better,” coach Marcus Freeman said. “There’s no magical formula. It’s work, it’s practice, it’s understanding the whats, the whys and the hows of executing on game day. It’s the belief in what we’re doing and in playing fast with velocity and violence.”

Right now, the numbers show no team understands those details better than the Irish.

They're yielding just 199.3 yards per game, the only FBS team allowing fewer than 200. They're allowing 8.3 points per game, just below Iowa at 8.0 and a fraction of last year's four-game average of 27.8. Plus, they've allowed just one second-half touchdown, that one coming with 6 seconds left in last weekend's 49-10 rout at Purdue.

They've done all that despite losing preseason All-American safety Brauntae Johnson and his replacement, Luke Talich, to injuries.

Just how good have they been? While the Irish have given up 23 points, the defense has nearly offset that total by scoring three touchdowns.

The criticism is that Notre Dame hasn't exactly played a murderer's row of opponents — Wisconsin, Rice, Michigan State and Purdue.

And the biggest test yet is the looming one against North Carolina (2-1), which is scoring 23.3 points and producing 366.0 yards, nearly half of that on the ground.

Yet for Notre Dame, playing a potentially stronger offense won't change its preparation.

“It’s going out and performing with intensity, not taking a rep for granted, whether it’s a coverage rep, a tackling rep, a pass-rush rep, a run rep, just a regular run," said Drayk Bowen, who returned a fumble for a TD last weekend. “That’s one thing that’s allowed us to play so fast. We go into a practice week with such a good intensity, you see it come out on Saturday. We recognize things. We play fast. We play physical. It doesn’t necessarily matter who the opponent is. We really think about it almost as a faceless opponent."

And by virtually any measure, Notre Dame has excelled.

The Irish have held five straight opponents to fewer than 100 yards rushing. Michigan State ran for just 40 yards, gaining zero in the second half. Rice produced only 128 total yards, the lowest total of any Notre Dame opponent since 2008.

Linebacker Jaylen Sneed believes the difference over the past 12 months comes down to experience both on the field and the familiarity with second-year coordinator Chris Ash.

“I think just having all the people come back really made it click,” Sneed said. “We were firing on all cylinders (late last year). We won 10 games at the end of the (2025). This year, we already know how to talk to each other, how to communicate with each other, how to play together. I felt like it just made it so much easier."

He added: “Since (Ash) came from the NFL, he hadn’t coached in college in a while. He had to learn how to talk to college kids again, learn how to work with college kids again."

The results are evident on the field, on the film and in the numbers that show Notre Dame's defense is one of the best in the nation, one potentially good enough to end a national championship drought that dates to 1988.

“Part of leaving no doubt is that mindset of going into practice every day, going to perform with that intensity, and then going out on the game and going to play to leave no doubt,” Bowen said. "It's making sure you’re doing everything you can to make sure that your team comes out on top.”

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