They had never worked together, yet there was still a familiarity between Atlanta Falcons coach Arthur Smith and his new defensive coordinator, Ryan Nielsen. It’s because of their general thoughts of football, which could be gleaned in how Nielsen’s defensive lines played and everything Smith has tried to create in his first two years in Atlanta.

While many of Smith’s hires have had some connection to his past, not all of them have, and Smith has made clear it wasn’t a prerequisite. He has always been about searching for fit and for people who can bring new and potentially innovative plans to what he has been trying to build.

In understanding how Smith and Atlanta landed on Nielsen to be their next defensive coordinator, it begins with the same buzzwords a lot of coaches say and Smith pushes to believe: aggressiveness, toughness, being physical.

“Those are all of the things that I believe in coming up through all of the places I’ve been,” Nielsen said. “You just take a little bit out of every place and every coach that you’ve been around, and you try to take the best of that and marry it into your philosophies.”

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There’s some understanding between Nielsen and his new bosses -- Nielsen worked with Falcons general manager Terry Fontenot in New Orleans -- but it’s making sure he and Smith have a good understanding of how they want to pursue defensive philosophies that’s most important.

The Falcons have wanted a better pass rush for years, since before Smith even arrived in Atlanta in January 2021. It hasn’t happened under Smith yet -- a combination of scheme, players and salary cap constraints have kept Smith from building the exact type of defense he wants.

With over $56 million in salary cap space for next season, the Falcons have money to bring in help for the first time, which should assist Atlanta with bringing in higher-caliber free agents, or at least pursuing them.

But no matter who Atlanta has, for Smith, hiring Nielsen came down to one thing: fit.

“I don’t care what system you’re running. You have to be able to adapt,” Smith said. “I was impressed with the plan with that, what we currently have and what we want to look to add and where we’re going.”

Smith believes Nielsen can do that. The Falcons want to stick with their hybrid, versatile model in base defense instead of a strict four-down lineman most plays, and Nielsen has particular experience with the defensive line.

At every place he has worked in his career, Nielsen has worked with the defensive line, from the lower levels of college football to the New Orleans Saints beginning in 2017. And he has had experience helping create a pass rush -- the area the Falcons have struggled with the most after 39 total sacks between the past two seasons.

“What he’s going to do is actually bring a pass rush,” Saints defensive lineman Cameron Jordan said on ESPN Radio's "Canty & Carlin." “Now he’s going to bring in some pass-rushers, and if not, he knows how to cultivate them. One of the best teachers of the defensive line that I’ve ever been a part of.”

Don’t be surprised if the genesis of Nielsen’s defense begins with strength and rotation up front. It’s a tenet Atlanta has been trying to build toward for the past two seasons. Be effective up front and flow from there.

That might not mean overloading, though. Smith and Nielsen want to potentially focus on run-stopping without committing too much to the front of the defense in terms of numbers, which would then leave Atlanta susceptible against the pass.

“Stop the run, and stop it in a light box, which is impressive if you don’t need to allocate resources to stop the run, if you can do that then you are playing pretty good run defense,” Nielsen said. “Attack, in everything that we’re going to do, we’re going to attack, and that’s in all phases of the defense, attack at every position.”

A lot of what Atlanta’s defense may look like, though, is still an unknown. It will form over the next two-plus months as the Falcons go through free agency and the draft.

“We don’t want to just blow everything up and start all over again,” Nielsen said. “We’re going to take what we’ve done well here the last couple of years. We’re going to implement some new things, put in some new ideas and just kind of marry it.”