SOUTH BEND, Ind. — The connection began about the time Francis Brewu got his driver’s license, back when he was still an undersized defensive tackle wondering what it would take to play college football. And it’s no mystery why Charlie Partridge made an impression. The career defensive line coach specialized in players like Brewu, taking three-star prospects and developing them into potential pros. The fact that Partridge was doing it at Pittsburgh, the football program that produced Aaron Donald, didn’t hurt, either.

However, just as Brewu was signing with Pittsburgh two years ago, Partridge left for the Indianapolis Colts. And maybe that’s when the relationship really began.

While developing into an all-ACC defensive tackle the past two seasons, Brewu reached out to the coach who had recruited him for tips. And Partridge always picked up, as if he’d never left, even if he knew he’d never actually coach Brewu.

“It’s absolutely huge because he wasn’t coming back to college football, you know what I mean? That was solely for the purpose of helping me grow,” Brewu said. “And most coaches would have just ignored me. … He easily could have not picked up or changed his phone number. Not responding to me when I reached out and whatnot, but he always responded. He always gave me his time to help me out.

“So knowing he still cared that much while he was at the next level played a huge part.”

Sure enough, Brewu will finally play for Partridge, whose return to the college game comes alongside comeback stories up and down Notre Dame’s defensive line. Partridge reunites with defensive coordinator Chris Ash. The two were college teammates at Drake and are now at their fourth different school together. Oregon transfer Tionne Gray gets a chance to play closer to his St. Louis home after the defensive tackle spent two seasons in the Pacific Northwest. There’s defensive tackle Jason Onye, who was granted a sixth season of college football after he missed more than half his junior year after leaving the team. And defensive end Keon Keeley gets a do-over with Notre Dame after de-committing from the Irish to sign with Alabama three years ago. He’ll reunite with two high school teammates: defensive assistant Tre Reader and cornerback Dallas Golden.

“I’ve gone through lots of ups and downs, and the only thing that you can do is continue to persevere,” Keeley said. “I just feel like this is a blessing to be in this opportunity, and I feel like it’s at the perfect time. There’s no better opportunity than to be here at Notre Dame.”

And of course, there’s Partridge and Brewu.

Brewu will not only get to play for Partridge at Notre Dame, but he will also be coached by an assistant fresh off a valuable two years in the NFL. Brewu gets a better version of Partridge, and Partridge gets a better version of Brewu.

“He’s learned how to coach at that level. He knows what the NFL demands,” Brewu said. “So now he can bring what the NFL demands and demand that from us. So we’re already prepared while we’re in college to go compete when our name is called at the next level. It’s huge.”

This is all part of the reason why Irish coach Marcus Freeman let Ash reshuffle the defensive staff, moving Al Washington to linebackers coach (before Washington left for the Miami Dolphins) and bringing in Partridge to upgrade the defensive line. After a season of lamenting that Notre Dame wasn’t getting enough pressure with four pass rushers and that the defensive scheme wasn’t always aligned between the front four and the back seven, Ash wanted a line coach fluent in his playbook. After stops together at Drake, Wisconsin and Arkansas, Partridge had that part down.

“Remember, what was the MTV show? ‘The Real World?’ Right? Stop being nice, start getting real. Me and Chris are way beyond where we have to be nice,” Partridge said. “We can have real conversations without an emotional barrier, come to a solution and there’s no problem.

“So there’s no ego that gets in the way with me and him. Because we’ve known each other so we can disagree and my respect for his vision on game day, that helps our back and forth.”

Notre Dame needs these relationships to work because in order to make a run in the College Football Playoff next season instead of just making the field, the defensive line can’t just be along for the ride. With a secondary that could be the best in the sport and a linebacker group that is more than capable, it’s the line that feels like Notre Dame’s biggest growth opportunity.

With Partridge taking over and Notre Dame adding Brewu, Keeley and Gray through the transfer portal, a position group that felt like a trip wire one month ago now looks more like a launching pad. The Irish return Boubacar Traore, Bryce Young, Elijah Hughes and Onye. The unit welcomes a four-man freshmen class that includes five-star defensive end Rodney Dunham. There’s more material than Notre Dame can realistically play, and it’s Partridge’s job to figure out the workload share. He’s a devotee of rotational play to a fault, unless there’s a star in the group who can’t come off the field. It remains to be seen how many of those Partridge might have.

“The way that we all, everybody in the room, can fit together and mix and anybody can play with anybody,” Brewu said. “I think we’re gonna go into the season and be one of the top five defensive lines in the country, if not the best defensive line in the country because of the people we got in there.”

That’s probably Brewu getting ahead of himself. Spring practices are still one month away. A season with real national title aspirations remains over the horizon. Still, this defensive line feels like it might be worth the wait. By reconnecting college teammates, reintroducing a former commitment and restarting a recruit-recruiter relationship, Notre Dame feels like it has the kind of defensive line the program needs.

No wonder the group can’t wait to get started, with Partridge leading the way.