FOXBORO — Matt Patricia’s unprecedented voyage toward the top of the NFL coaching circuit has been forged by the total embodiment of his unique background.

Patricia, the defensive coordinator for the Patriots, left a well-paying job in his engineering field to gain an education with a series of low-paying, entry-level coaching gigs. It wasn’t, nor could it have been, about the money as much as a passion to accumulate the necessary experiences and exposure that could yield a greater future.

And since joining the Pats staff in 2004, Patricia has been responsible for transitioning coach Bill Belichick’s football operations into the 21st century with his technological prowess by computerizing the film documentation. Patricia was also able to bring the clock on Belichick’s car stereo into the modern age. When Belichick’s clock was temporarily doomed by daylight savings time in 2009, he summoned the resident rocket scientist to work his magic.

More importantly, Patricia has seized control of Belichick’s defense and turned it into a unit that is ranked eighth in points (19.7 per game), seventh in yards (332.8 per game) and second in sacks (48) this season, and the Pats’ 116 takeaways since he took over as the coordinator in 2012 are tied for the second most in the NFL. Pending Sunday’s regular-season finale in Miami against the Dolphins, it could statistically be the team’s best defense since 2009.

Now, quite possibly for the first time, Patricia could be requested to interview for head coaching vacancies next week while the Patriots enjoy a first-round playoff bye.

The opportunity will be two decades and a lot of head-scratching decisions in the making. But with every opportunity the 41-year-old Patricia turned down, his friends, bosses and colleagues wiped away a relative level of shock with the trump card: They knew that bearded guy with the aeronautical engineering degree from Rensselaer Polytechnic Institute was always the smartest one in the room, and Patricia’s plan always had a purpose.

Start from the bottom

Like Belichick, Patricia played center for his college football team. Then, rather than taking a lucrative job in his field after graduating in the fall of 1996, Patricia wanted a role on the coaching staff, so RPI coach Joe King offered an internship.

“To come back here and give all of that up (as an engineer) for basically nothing, very low pay and all of that,” King said. “I told him, ‘Do you understand what a move this is?’ He said, ‘Yeah, this is something I want to do.’ He was obviously pretty committed to it.”

Patricia couldn’t turn the RPI internship into a full-time coaching position, so he spread out in 1997-98, making good money as an engineer while trying to gain some face time with Paul Pasqualoni’s staff at Syracuse. Patricia volunteered during spring camps, picking up players at the airport, working security in the dorms, running curfew checks and setting up cones for field drills.

“No job too small,” Pasqualoni said. “He showed a great love for football. Beyond love, a real passion for football.”

In 1999, Patricia worked a connection to land on coach E.J. Mills’ staff at Amherst College. He had to surrender a lucrative engineering salary to make $8,000 as the defensive line coach. Mills, who doubled as the defensive coordinator, recognized Patricia’s high aptitude, so he brought him to a new side of the ball to keep him under his wing.

Right away, Mills knew Patricia could relate to every player and coach on a personal side, which has always been one of his greatest assets off the field, and he could break down offensive and defensive concepts that were necessary for on-field success.

But Patricia, the son of two teachers, loved to put his knowledge of computers to work as much as anything, and that was incalculably helpful for Mills’ staff during Patricia’s two seasons in Amherst. Patricia taught Mills how to utilize Microsoft Excel and PowerPoint to the program’s benefit at a time when that type of software resembled a foreign language. Plus, as Belichick would grow to appreciate years later, Mills always got a kick out of asking Patricia to set up his stereo equipment.

Alternative route

Patricia encountered another major decision in 2001 when Saint Lawrence offered him a job coaching the offensive line, which would have paid him somewhere north of $30,000, but he was too unconventional to take the gig. Instead, he accepted an offer from Pasqualoni as a non-paying graduate assistant in the film room.

Having grown up in the area, Patricia was enamored by the idea of a big-time Syracuse program. Patricia followed his heart despite Mills’ advice to head to Saint Lawrence.

“I told him, ‘Dude, I think you’re nuts. I would take that job at St. Lawrence,’ ” Mills said. “He didn’t listen to me, and that was a good move. I think Matty had a burning desire to be at the highest level.”

Ultimately, it was a perfect move for Patricia. Under Pasqualoni and offensive coordinator George DeLeone, coaches learned to be committed for 24 hours a day, and that work ethic was instrumental down the road in New England. But with Syracuse, Patricia logged film of opposing defenses and streamlined it for the offensive coaches, tracking formations, personnel packages and blitzes by down, distance and field position, and Pasqualoni wanted the information documented precisely or it was, by his description, “worthless.”

For Patricia, it was self-fulfilling because he viewed experience as currency.

“His work ethic was fantastic, would work at it until the job got done. Hours were not an issue,” Pasqualoni said. “Matt was like he wasn’t at work. He was doing what he loved to do.”

Family matters

Patricia was worried he made a crucial mistake during a phone call with Belichick before accepting a job with the Patriots in 2004. Prior to his final decision, Patricia said he wanted to talk it over with his family, and that haunted him when he hung up, fearing Belichick would question his commitment.

Pasqualoni calmed him down in the Syracuse coach’s office and, obviously, it worked in Patricia’s favor. That’s who Patricia is — a family man who cares about people as much as football, and that aided his progression with the Pats.

Oh, and don’t forget about the part of him being a rocket scientist.

“To be at RPI, to be an engineering student at that level with that math background, he’s just working on a different level than most humans,” Mills said. “He certainly doesn’t look that part, but it doesn’t take long to figure out this is a smart guy who has a little bit more going on in his head than most. I remember saying to him, ‘That’s going to be your edge, dude.’ ”

Patricia joined the Pats as an offensive assistant and somehow convinced Belichick to scrap the pencil-and-paper method of logging film in favor of a computerized system. He put together a presentation to show how much more the coaches could do if they accepted the advanced technology. So when Belichick said recently Patricia “could probably build a plane and fly it,” from a relative standpoint, that’s already been accomplished in the coaching offices at Gillette Stadium.

Patricia needed to prove himself to a core group of players who were coming off a second Super Bowl, too. That was just as natural for him, as the players instantly recognized Patricia was smart, humble and dedicated to both the job and the people.

“How he won me over, we got really close, just me and him talking every day, talking in the morning, small conversations, nothing big, talking about the offense,” former running back Kevin Faulk said. “We talked about football and family.”

Belichick promoted Patricia to Dante Scarnecchia’s assistant offensive line coach in 2005, where he worked alongside a legend while focusing on a more familiar position. Make no mistake, Patricia remained in Scarnecchia’s shadow, but the players appreciated the methodical way he studied and relayed necessary information on a daily basis.

“He has an aeronautical engineering degree. It’s not like he was in Basket Weaving 101 and took over a coaching role because he was grandfathered in or something,” former left tackle Matt Light said. “He’s just a great guy, an all-around great person. It’s easy to get along with a guy like that. We’re a special breed as offensive linemen, and he fit in well.”

And then, it was time for the big move.

In the middle of things

Patricia began a five-year run as the linebackers coach as a 31-year-old in the 2006 offseason, so he took over a room that included the likes of Tedy Bruschi, Mike Vrabel, Rosevelt Colvin, Larry Izzo and eventually Junior Seau. Because Belichick is a linebackers coach at heart from his days with the New York Giants, he attended meetings, watched Patricia’s development and had his back whenever necessary.

“I joked,” Mills, who has remained close with Patricia, said. “I called him and said, ‘Who the hell are you kidding? You’re coaching Tedy Bruschi, Mike Vrabel. What the hell are you telling those guys?’ And he laughed.”

This was the first sign Belichick had bigger plans for Patricia, who had never before formally coached linebackers. But this was where Patricia’s background dearly paid off in terms of dissecting information and then teaching from it. Patricia certainly wasn’t called upon to teach Bruschi how to tackle, but that group of linebackers wasn’t interested in wasting time.

When the linebackers arrived Wednesday mornings for their first official meetings of the week, Patricia would have already watched upward of 48 hours of film if that’s what was required. To Patricia’s credit, he took charge of that room.

“You’ve got to be witty. You’ve got to be quick,” Colvin said. “You’ve got to have a lot of brain capacity. That’s what we had, a lot of smart guys in the room. When we asked a question, it’s because we really don’t know the answer.”

Patricia thrived and continued to earn more responsibility over the years, and he was often seen alongside Belichick in offseason scouting trips. But Patricia never altered his approach with the players, as they were all family to him.

Light, the greatest practical joker of the Belichick era, still cracks up over one particular training camp story. The offensive lineman and some teammates were grabbing lunch at Patriot Place during a break, which coincided with an important coaches meeting, when Patricia managed to escape the meeting room to call Light in hysterics.

The coaches were reviewing film from that morning’s practice when they noticed a grown man who was stationed under the play clock wearing Daisy Dukes and holding pompoms and cardboard signs. Patricia assumed it was Light’s doing, and he had to let him know that every coach except Belichick thought it was hilarious.

“He called me crying laughing on the phone to the point where he had to excuse himself from the meeting,” Light said. “That was one of my favorite moments, getting the phone call from him.”

Light played it off at the time, but he appreciated that Patricia never sold him out.

Command post

Patricia shifted to coach the safeties in 2011 and was officially promoted to defensive coordinator in 2012. Still, at that point, the players recognized it was Belichick’s defense, but Patricia has gained far more command of the room over the past two or three seasons.

Patricia, without ego, has been successful at each stop because of his consistent ability to teach and relate to people, evidenced publicly before every game when he marches through the stretching line to hug every player in sight. Those are the qualities of a great coach, regardless of title.

It seems like outsiders are noticing, but the true vindication will be whether Patricia is requested for interviews in January. Patricia has been taking chances on himself throughout his life, and the aeronautical engineer has also received an extended education in coaching.

Eventually, if another NFL team takes its own chance on Patricia, the organization will uncover what so many have learned along the way.

“I think he’d be very well-suited to be a head coach one day,” Light said. “The coaching world in the NFL is a little bit of the good old boy world. He is definitely one of those who could break into it and probably do some pretty incredible things if he was so inclined.”