INDIANAPOLIS, Ind. – He was ready to take that last step after having done the required preparatory work. He was that 41-year old defensive coordinator who had taken notes and gleaned every bit of information possible while working alongside Chuck Noll, Marty Schottenheimer and Dennis Green, all the while planning for that moment in time.

Tony Dungy made the leap from coordinator to head coach in January 1996 when the bottom-feeding Tampa Bay Buccaneers looked to a fresh face for a fresh approach.

It didn’t take long for Dungy to realize he had entered a new universe, one that revealed on a daily basis how much he didn’t know.

A few days after settling into his new office, his attempt at finalizing his staff was interrupted as a Bucs employee entered.

Oh, I’ve got to talk to you right now, coach. Right now!

The urgency?

“He needed to know what airline we’re going to charter and what hotels I wanted to stay at,’’ Dungy told Indy Sports Central. “He told me, ‘I’ve got to make these hotel reservations right now before we lose them.’

“That’s the last thing in the world you’re thinking about. You’re like, ‘Can I talk to Herm Edwards so I can see if I can get my DB coach on board before we sit down and try to figure this out?’’

One of Dungy’s first priorities in Tampa was to meet with his veteran players. The new head coach wanted to introduce himself to everyone, but also get input on reasons the franchise had endured 13 consecutive losing seasons.

Linebacker Hardy Nickerson, one of the Bucs’ pillar players, had scribbled down his ideas on three yellow legal sheets of paper.

“It was crazy stuff, like, ‘They took the Coke machine out of the locker room. We used to get free Cokes and now we don’t and that’s got everybody upset,’’’ Dungy said. “So that was a day of (asking the team), ‘Why did we take the Coke machine out of the locker room? Give me the history of it. What can we do?’’’

Dungy laughed as he recalled the Nickerson moment, the meeting to deal with travel logistics and so many situations that dealt with issues that never – ever – were on his radar during his 15 NFL seasons as a coordinator or position coach.

But he quickly insisted they were no laughing matter.

Before settling into his first head coaching gig, Dungy’s focus solely was on the 30-some-odd defensive players under his coordinator’s umbrella.

“You’re focused on making that unit work as well as it can,’’ he said.

In the blink of an eye, the lens expands from condensed to wide-angle.

Dungy represents a voice of experience for the current scenario unfolding across the NFL landscape. The common denominator shared by the primary cast of candidates for coaching vacancies: a lack of head coaching experience, at any level.

New England offensive coordinator Josh McDaniels, who met last week with Indianapolis Colts general manager Chris Ballard, was the Denver Broncos’ head coach for two seasons and 28 games before being fired in 2010. That’s it.

The others have zero experience overseeing an entire football operation: Kansas City offensive coordinator Matt Nagy, hired by the Chicago Bears Monday; and defensive coordinators Mike Vrabel of Houston, Kris Richard of Seattle and Steve Wilks of Carolina.

The Colts reportedly met with Vrabel and Richard last week. They’re expected to meet with Wilks Thursday, unless he’s scooped up by another team prior to that. Wilks met with the New York Giants Tuesday and has a scheduled meeting with Arizona Wednesday.

Each candidate has been adept at his area of expertise, which is why he’s being considered for something much bigger.

But do Nagy, Vrabel, Richard, Wilks or any other prospect lacking head coaching experience fully comprehend the challenge ahead?

“You get into that seat and there are so many things that happen that you aren’t ready for, that you can’t know until you experience being the head coach,’’ said Dungy, the winningest coach in Colts’ history and a member of the Pro Football Hall of Fame’s Class of 2016. “There are the media demands. All of a sudden you’re the face of the franchise. There are so many non-football things you have to deal with.’’

In his role as NBC analyst, Dungy interviewed Los Angeles Rams coach Sean McVay last week prior to his team’s wild-card playoff game. McVay, 31 at the time, became the youngest coach in NFL modern history when the Rams hired him in January 2017. McVay’s NFL experience consisted of eight seasons with Washington, the last three as offensive coordinator.

McVay found out quickly the enormity of the job, and how it involved more than forming the right staff and not screwing up on game day.

“Sean was laughing and telling me about having to pick out furniture for the office and what color the paint was going to be on the building,’’ Dungy said. “I remember the same thing.

“There are things you just can’t get prepared for until you go through it.’’

What’s going on with the players, all of them, not just the segment you dealt with as a coordinator? What responsibilities are yours as head coach, and which can be delegated? How will you arrange the team’s daily schedule? When do you meet during the week with the owner? The GM? Which pre-draft workouts should you and your staff attend? When’s lunch, dinner?

“None of those things have been on your radar,’’ Dungy said, “and they all take a little bit away from you. All of a sudden you become aware of everything that’s going on.

“You’ve got to be the final say on a lot of things you hadn’t even thought about. It’s something you have to get used to.’’

Arguably a new head coach’s most important chore is settling on his coordinators and staff. Rest assured McDaniels or Wilks has a list of assistants they want to bring with them, wherever they land.

But be prepared to adjust.

“You have thoughts and ideas,’’ Dungy said. “For two or three years you’re thinking, ‘If I get this job, these are the guys I’d like.’ Then some of those guys are under contract and can’t come with you. Or a guy who you thought would be with you gets a head coaching job or gets a college head coaching job so he’s off the table. Now, where do I go? Putting your staff together isn’t as easy as it seems.

“More than anything, it’s all the different things that go along with being a head coach, the decisions on things you never thought of, that Dennis Green decided on and never crossed my mind that I was going to have to deal with.’’

So how does Ballard properly vet candidates who have zero experience as a head coach?

“That’s the million dollar question,’’ Dungy said. “You can find plenty of guys who have a good scheme and are great at Xs and Os and the players like them and they’re excellent at what they do.

“But that’s not being a head coach. There’s so much that goes into it before you even talk about the game management and motivating people you have to do during the season.’’