For the 2nd straight offseason, the USC football team renovated its defense through the transfer portal, mining some of the most prolific programs in the country in the process.

In marched guys like Anthony Lucas of Texas A&M and Mason Cobb of Oklahoma State, Jack Sullivan of Purdue and Tre’Quon Fegans of Alabama, Kyon Barrs and Christian Roland-Wallace of Arizona, Jamil Muhammad of Georgia State and Bear Alexander of Georgia.

Adding this collection of talent to last year’s haul in Lincoln Riley’s debut season — guys like former Colorado cornerback Mekhi Blackmon, former Arizona State linebacker Eric Gentry, former Ohio State safety Bryson Shaw, former Auburn linebacker Romello Height and former Alabama linebacker Shane Lee — was supposed to be the salve for a defense that licked its wounds after a terrible end to last season.

We were told all spring and all fall camp that USC was simply missing a few key pieces, that its defensive turnaround was just around the corner.

We were told that Alex Grinch had learned the error of his ways, that the Trojans would play a different, calmer, better brand of football in 2023.

That lasted about 14 minutes on Saturday night.

On a 3rd-and-22 from the USC 39-yard line late in the 1st quarter, talented quarterback Chevan Cordeiro, the Mountain West preseason player of the year, snuck though an onslaught of blitzers to escape for a 28-yard gain, setting up a 1-yard touchdown 4 plays later and tying the game at 7.

The only thing different from 2022?

Some of the jersey numbers had changed.

“The quarterback is a good player,” Riley told reporters after the game. “We had a spy on him a lot of times. A couple of times, we got lost in there and got a little too aggressive. A couple of times, he just flat-out outran us. He’s a good player. That was the disappointing part. The penalties and the busted coverage before half are the things that were frustrating. It had the makings of being a good defensive performance. But those are the mistakes you have to correct.”

Same over-pursuit. Same poor timing. Same lack of discipline.

Same old Trojans.

*****

Around 6:40 p.m. on Saturday night, not long after that busted call was followed by a 10-yard Quali Conley run that featured many of the same ills, I got a text from Southern California High School head coach.

“Your Tweet was funny. Their last two plays of that drive were ridiculous. He called a man look drop to cover 2 that was horribly executed. Trying to be too cute. That may have athletes, get in your base D and execute it well. The SEC way.”

It’s as plain as day to anyone watching.

It’s not the talent.

We can all agree on that, right? Not the talent?

That leaves 2 things: Scheme and play-calling, and those point directly to Riley and Grinch. It’s not fair to just blame Grinch for USC’s follies. These issues date back to Riley’s Oklahoma days, when he lit up the scoreboard all year, only to falter against great teams in the Playoff.

“Everybody is going to write the narrative after the first game. It’s going to be a climb. It’s going to be a climb,” Riley said. “I like what I see out there in terms of our good plays, how our guys are flying around, and the depth that we have. We will continue to improve the baseline for that group. The ceiling for that group is much higher than it was 12 months ago. No matter what the score was … If this was a 3-point game, 28-point game or 50-point game — there’s going to be that climb to the next step. That’s where our focus is going to stay. I love what we have in there. We have a lot of work to do, and we’re the right people to get it done.”

Or is it a third thing?

I remain unconvinced that you can transfer-portal your way to a good defense. Offense leads with skill, defense leads with discipline. Offense relies on talent, defense relies on cohesion.

*****

Defensive breakdowns happen when defenders try to do too much.

USC was always at its best when it kept it simple and relied on its talent to make spectacular plays within the realm of their roles and responsibilities. Sure, it’s fun to watch Trojans like Tuli Tuipulotu rack up a bunch of sacks and DBs like Calen Bullock pick off a bunch of passes. But that’s not always winning football, and you certainly can’t count on those kind of dynamic plays.

Saturday, a USC defense that averaged 2.86 sacks per game and boasted the best turnover margin in the league by a massive margin last year had precisely 1 sack and zero takeaways.

Worse, the Trojans allowed 198 rushing yards and 7.3 yards per carry.

If USC is going to vie for a College Football Playoff berth this year, they’ve got to fix what ails them and soon.