SOUTH BEND, Ind. -- Marcus Freeman won't be taking over the Notre Dame defense.

He won't admit it anyway, as the Irish (0-2) attempt to restart their season on Saturday afternoon (3:30 p.m. ET, NBC) against in-state rival Purdue (2-1) and first-year head coach Barry Odom. Still, Freeman won't accept a repeat performance on the side of the ball he specializes in, no matter how much faith he continues to express in defensive coordinator Chris Ash.

"What am I, as the head coach, willing to tolerate?" Freeman said. "I have to demand that everything we've set as our standard (is) met. That's what I have to continue to do. If I need to be involved more in a certain area, then I will, and I am."

That requires little reading between the lines. In last weekend's 41-40 loss to Texas A&M, Notre Dame's defense allowed Aggies quarterback Marcel Reed to throw for 360 yards, and he could have topped 500 if he'd hit a couple more deep shots. The Irish didn't sack him once and rarely got pressure. There were coverage busts and broken run fits. Notre Dame made it all too easy for Texas A&M, right down the game-winning touchdown on fourth-and-11 with 13 seconds remaining.

The issue for Notre Dame is how much Freeman can really fix in a week, considering the pressure on the program coming off a run to the national championship game. There aren't many personnel changes to make. Starting cornerbacks Leonard Moore and Christian Gray are both playing through pain. The defensive line has struggled to affect quarterbacks. And the specifics of who plays when and how much in the linebacker rotation feel like they're up for debate.

"I could get up here and say it's execution, and it is, but what does a lack of execution come down to?" Freeman said. "It could be a lack of focus, a lack of proper technique, a lack of understanding what's expected, a personnel issue where you're asking somebody to do something that they can't do consistently. All those things are the responsibility of us as coaches."

That falls on Ash. It falls on Freeman, too.

On Saturday afternoon, Notre Dame can take the first step forward in a season of false starts. The defense doesn't need to carry the day, but it has to start being part of the solution.

Here are three keys and one prediction for Notre Dame's matchup with Purdue.

Considering Carr's pre-snap stance tipped Texas A&M off to whether Notre Dame would run or pass, the Irish quarterback picked apart a secondary that sort of knew what was coming.

Making his second career start in a game when Notre Dame needed to air it out, the sophomore went 20 of 32 for 293 yards, one touchdown and one interception. He pushed the ball vertically. He layered throws over zone defenders. He stood in the pocket when Texas A&M collapsed it. Even if there were a few freshman moments, including another intentional grounding call and that botched end-of-half sequence when Carr's clap of frustration trigger Ashton Craig's snap, his performance represented a step forward.

"It just shows you, like, you get thrown into the fire against two opponents like that, you don't know what you're getting out of a freshman quarterback when you put him out there for the first time," said quarterbacks coach Gino Guidugli. "And to kind of respond and play with as much poise as he does, I think he's got a chance to be a really good one. I think he's going to continue to get better, and offensively we'll be better for it."

As good as the stat lines have been, Carr's composure under pressure might be what has resonated within the offense most. He has had to shake off major hits and major mistakes. And he seems to do both with little effort.

"When you make a mistake, you can't dwell on it, you gotta move on, and that's what he does," said tight end Eli Raridon. "It's really hard to learn that at a young age, and he's so mature. I can't even compare myself to (that), he's playing quarterback, so I can't even imagine."

No player got a bigger workload bump from Game 1 to Game 2 than sophomore safety Tae Johnson. The player who flashed on the opening day of training camp with two interceptions of Carr may have just gone from rotational player to full-on starter. After logging just nine snaps at Miami, Johnson got 56 snaps against Texas A&M. Now he's set to start against Purdue, with captain Adon Shuler suspended for the first half after a targeting penalty in the second half last Saturday.

"I thought Tae did a good job being out there," Freeman said. "He made some plays, some really good open-field tackles and made some plays on the ball. He's a talented individual. He was going to get more, no matter what, but with Adon being out a half, he's going to have more on his plate, and he's going to do just fine with it."

Notre Dame needs more playmaking from the back of the defense, which continues to struggle to replace two-time All-American Xavier Watts. That's not what Notre Dame is asking of Johnson, who took a redshirt last season. But the Irish need something more than what they're getting from Virginia Tech transfer Jalen Stroman and former walk-on Luke Talich. Stroman was beat badly on Mario Craver's 86-yard touchdown and didn't help on the deep shot to KC Concepcion over freshman cornerback Mark Zackery.

Through two games, Notre Dame's safeties have accounted for just one havoc play. That's tackles for loss, force fumbles, interceptions or passes broken up. Johnson's PBU against Texas A&M was that one play.

Last season, Watts and Shuler combined for 32.5 havoc plays.

"We just gotta fix our stuff and play with clarity and violence," Shuler said. "We can't listen to what everyone is saying. What the coaches say and what Coach Free says is really the main thing, because we're the ones on the field and no one else can go out there and do what we do."

The performance will get lost in the final score, but Notre Dame found something with Virginia transfer Malachi Fields against Texas A&M, with 11 targets that turned into five catches for 77 yards. That's not an ideal catch percentage, and if Fields caught that slant route for a touchdown at the goal line, maybe the game would have ended differently. But that target total is the most by a Notre Dame receiver since Kevin Austin's dozen against Oklahoma State in the Fiesta Bowl, which was Freeman's first game in charge.

At 6 foot 4 and 222 pounds, Fields is a prototypical boundary receiver, and Notre Dame is using him like one.

"He's obviously extremely talented, a guy that we've identified that we have to find ways to get the ball into his hands or at least attempt to throw the ball his way because he's really good," Freeman said. "A lot of times, he's going to make that play."

Fields wanted that incomplete slant route back and admitted he could have used a different technique to make the catch from Carr. Yet, Fields also showed a knack for sitting down between cornerbacks and safeties in zone coverages, the kind of thing that doesn't come easily in the two games with new quarterback. At least most of the time.

Even within an offense where there aren't enough targets to go around -- Jaden Greathouse, Jordan Faison and Will Pauling have combined for just 11 catches, with Faison accounting for seven of those -- Fields feels like the receiver who has to get his for the passing game to function. For a player whose first touch of the season was a lost fumble, Fields has had no issue bouncing back since.

Carr may never admit to having a favorite target, but Fields would likely get that vote.

"I usually just tell him, give me a chance," Fields said. "I'll go make a play for you. But just some things we got to keep working on so we can execute and get balls caught."

Put the final score aside for a moment. The most important item on Notre Dame's to-do list on Saturday afternoon is figuring out what the defense can actually do well. It's been a grab bag of mistakes against Miami and Texas A&M, and last year's No. 1 pass efficiency defense now ranks No. 103 entering Week 4. Is it an issue of play calling? Personnel? Scheme? It's probably all of the above, no matter how much Freeman talks about execution as the most important fix. Notre Dame's defense needs to do less but do it better against Purdue. And although the Boilermakers are now a serious football program again, that shouldn't be too high of a bar for the Irish defense to clear.

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