Two days after their 25-point collapse in the Super Bowl, the Atlanta Falcons relieved defensive coordinator Richard Smith of his duties. Secondary coach Marquand Manuel is a favorite to replace Smith, but no matter what the Falcons do with the coordinator role, the unit shouldn’t miss a beat.

That’s because midway through the season, Dan Quinn took over play-calling responsibilities from Smith, and he will likely continue handling those duties next season.

The defense had been a weakness for the Falcons for several years. Since a 2011 postseason implosion against the Green Bay Packers, the Falcons emphasized adding talent on the offensive side of the ball, and the result was a lopsided team. That’s part of the reason Quinn, a former defensive coordinator, was an appealing hire for Atlanta.

Since Quinn’s arrival, several elements of his approach have helped shape and improve Atlanta’s defense. Quinn’s decision to take over play-calling was the final push that helped this young defense become contenders.

The Falcons were taking a gamble heading into the 2016 season. They had slotted three rookies in starting roles — first-rounder Keanu Neal at strong safety, second-round pick Deion Jones at middle linebacker, and fourth-rounder De’Vondre Campbell at weakside linebacker. Rookie nickelback Brian Poole, an undrafted free agent out of Florida, was essentially a starter given how much time Atlanta spends in the nickel package.

On top of that, the Falcons had second-year players Vic Beasley and Grady Jarrett, as well as cornerback Jalen Collins, who was pressed into action after Pro Bowl cornerback Desmond Trufant suffered a season-ending shoulder injury.

The scheme the Falcons run is Quinn’s, and he is adept at anticipating his opponent and making adjustments. But with that much youth on the field, some lapses were to be expected. In the first 10 weeks of the 2016 season, the Falcons’ inexperienced defense struggled. That’s when Quinn took over.

Quinn was the catalyst for defensive improvement

There came a turning point after the Week 11 bye, when the defense saw dramatic improvement. That can be attributed, in part, to the young players settling in and improving communication.

“I think after that bye week, we skyrocketed, and we’re a lot better defense now,” Neal told SB Nation prior to the playoff win over the Seahawks. “We’re a lot closer, it seems like, like our chemistry’s a lot better, and we’re playing more like a united defense, and you can see that.”

It wasn’t just the assimilation of young players into this defense and the NFL. It was also Quinn’s play-calling.

NumberFire analyzed the defensive performance before and after the Week 11 bye, and there was a marked difference. The Falcons allowed 385.9 yards per game in the first 10 weeks, but after the bye week, that number was all the way down to 346.67 yards per game.

Perhaps the biggest difference was in points allowed per game, which dropped from 28.3 before the bye to 20.5 after it. That post-bye number would have tied them with the Houston Texans right outside of the top 10 for points allowed.

The Falcons also upped the number of takeaways per game — which is always an emphasis for Quinn — from 1.57 per game before the bye to 1.83 afterward.

Quinn’s takeover of play-calling duties made Smith expendable.

Why Manuel?

Manuel did wonders with a secondary that lost Trufant, its best player. Outside of veteran cornerback Robert Alford, Manuel was working with a converted cornerback at free safety in Ricardo Allen. He had rookies, Poole and Neal, at nickel and strong safety, and then Collins filling in for Trufant.

Quinn works well with Manuel and respects the way he approaches coaching up his players.

“It’s the communication, the training, he doesn’t back off,” Quinn said. “The players know that. They’re very perceptive. All players are. What can I get away with him? Not very much. We’ve got lots of respect for the way Marquand takes care of his side.”

Quinn also likes Manuel’s competitive nature.

“Yeah, his fire’s lit, and it does not go out. He’s a really passionate guy,” Quinn said. “Honestly, it’s just somebody that’s always constantly challenging to see if it can get done a little bit better. And honestly, that’s what the essence of a competitor is.”

With so many young players on defense and the incremental improvement in this unit’s play over the course of the season and the postseason, the future is bright in Atlanta.

And while it may seem odd for the team to part ways with its coordinator when there were late-season improvements in most categories and a drastic turnaround in the team’s ability to rush the passer, it makes sense. Richard Smith wasn’t the reason for the improvement. Dan Quinn was.

Quinn still needs to maintain a big-picture perspective as head coach, so it’s unlikely he’ll forgo hiring a defensive coordinator altogether. Manuel seems to be a likely choice based on his experience there and his relationship with Quinn.

But don’t be surprised if Quinn continues calling plays in Atlanta. His involvement was a primary reason for the defensive surge and was a key factor in helping the team get to Super Bowl LI.