No single play from the Falcons’ 44–21 win over the Packers in last Sunday’s NFC championship game rocked the Georgia Dome quite like Julio Jones’s 73-yard touchdown romp early in the third quarter. As Jones snagged a pass over the middle, shrugged off one Green Bay defender, and stiff-armed another into a different dimension, the building seemed ready to shake off its foundation.

It was just one of the countless otherworldly feats Jones performed that afternoon, as he finished with nine catches for 180 yards with two scores. But as he was doing his best Paul Bunyan impersonation, Atlanta’s offensive line was quietly showing how it, too, has helped make the Falcons’ Super Bowl run — and all-time great offense — a reality.

At the snap before Jones’s touchdown, all of Atlanta’s linemen slid their protection to the right, ignoring the defenders lined up directly over them to pick up the men one gap over. With tight end Levine Toilolo screaming across the formation to the left, the tactic worked to perfection, a seamless blitz pickup coordinated with confidence and authority. And in the middle of it all stood Alex Mack.

“One of the first things I noticed is ‘Man, he’s on top of everything,’” says Falcons left tackle Jake Matthews of Mack. “He wants to know the answer to every look, every scenario. I think that’s really paid off for us.”

In piecing together what’s made this unit the highest-scoring offense in football and one of the most terror-inducing squads in league history, people are quick to mention a familiar cast of characters: an MVP quarterback, a receiver from another galaxy, and a play-calling mastermind of an offensive coordinator. Just as vital, though, has been the arrival of All-Pro center Mack, and the cohesion he’s brought to this offensive line.

“I think you can kind of see [Mack’s influence] this year with the transformation Atlanta’s gone through,” says Chiefs right tackle Mitchell Schwartz, who played with Mack for four seasons in Cleveland from 2012 to 2015. “Obviously, Julio [Jones] is playing amazing and Matt Ryan’s having a career year, but I think that’s all kind of linked to their offensive line stability and [Alex] going there and stabilizing it, just like he did for us [on the Browns].”

On Tuesday, it was revealed that Mack wouldn’t practice this week — a precaution to give his injured fibula time to heal before the team arrives in Houston, and the same treatment being afforded to Jones for his toe. In the leadup to the most important (and only the third playoff) game of his career, Mack is being handled like a star, offering a window into just how valuable he’s been during the course of his first season with Atlanta. Others will get awards, promotions, and entire stadiums chanting their names. But in unlocking the Falcons’ unlimited firepower, Mack has been the key.

It seems silly, when taking a look at the season-long stats, to suggest that the 2014 Browns offense was exceptional. Cleveland finished that year ranked 27th in points per game (18.7), and its advanced metrics aren’t much better, as the Browns were 24th in Football Outsiders’ offensive DVOA, 28th in points per drive, and 31st in three-and-outs per drive.

Early in the season, though, the Kyle Shanahan–coordinated Browns were cruising. Cleveland put up 26.8 points per game throughout its 3–2 start, ranking second in offensive DVOA and averaging 4.4 yards per carry, the 12th-best mark in football. “We had a really good thing goin’,” says Browns left tackle Joe Thomas. “I think in my 10 years [in the league], that was the best offensive line that we’ve had. We were rolling, and when Alex got hurt, it changed everything.”

In the Browns’ 31–10 win over the Steelers in Week 6, Mack got stuck in a pile after a play and broke his left fibula. Surgery followed, and Cleveland placed him on the injured reserve shortly thereafter. Lacking Mack in the middle, the offense cratered. Shanahan’s group closed the season averaging 3.6 yards per rush, a sharp dropoff from its red-hot start. After scoring at least 26 points four times in their first five games, the Browns hit that total just once in their final 11 outings.

Thomas says the effect of losing a player like Mack was twofold. At 6-foot-4 and 311 pounds, Mack has uncommon physical traits for a center, and the talent decline from him to guys such as Nick McDonald and Ryan Seymour (neither of whom has started an NFL game since the 2014 campaign) was steep. An even larger problem was the way the Browns’ communication crumbled. Without Mack there to deliver instructions and keep the line’s assignments in sync, Cleveland’s offense sunk. “We’ve got a center in there who doesn’t know who he’s supposed to point to, the line calls — it just throws off your coordination and your timing up front,” Thomas says. “Those little tiny blips that maybe a fan doesn’t think is a big deal turn into a minus-3-yard run on first down, and that can ruin your whole drive.”

As is the case with so many quietly great players, Mack’s value was only properly understood when his team faced life without him. NFL defenses rarely present a straightforward challenge, and without Mack around to steer Cleveland’s offense back on course when it faced a wonky front or a look it’d never seen, all the other cracks on the roster began to show. “Alex is always so good at telling everyone where to go,” Schwartz says. “He does it very strongly. There’s no consternation. There’s no confusion. When the rules get hazy … I think that was a huge factor.”

Mack’s eventual exit from Cleveland was notably bizarre, especially for a player of his stature. Because the Browns placed the transition tag on him when he was set to enter free agency in 2014, the Jaguars were allowed to offer him a five-year deal with a host of unusual provisions, in an effort to make it as difficult as possible for Cleveland to match. Only the first two years of Mack’s contract offer from Jacksonville were guaranteed, and along with featuring a no-trade clause for the first three seasons, it gave Mack the option to void the deal following the 2015 campaign. The Browns ultimately matched, but there was a sinking feeling that Mack would bolt for a more stable environment the moment he had the chance.

Last spring, that meant coming to Atlanta on a five-year, $45 million deal that made him the richest center in the NFL. “I was really excited to be in this scheme because it’s one I knew, and I knew I could be successful in it,” Mack says. “I know it fits my style of play really well.”

Part of Mack’s value comes from his ability to organize and inform his linemates, but when the Falcons gave him $28.5 million guaranteed last March — more than anyone at his position — they were paying for a lot more than his brain. His combination of physical talents makes Mack a rare find, and in 2009 it made him one of just nine centers taken in the first round of the draft this century.

For one thing, he’s taller and heavier than most centers. Even compared to other offensive linemen, his massive shoulders and Superman-like chest are almost cartoonish. “Centers are usually smaller guys,” Thomas says. “He’s a big, strong guy. I think his combination of power and the effort he gives is unique, and part of the reason it makes him the best center in football.”

Mack’s level of bulk could be problematic for many centers in Shanahan’s outside-zone running scheme, one in which quickness matters above all else. Shanahan prefers to avoid using two-man-combination blocks — a double-team followed by a lineman moving to the second level toward a linebacker — whenever possible. That makes a center who can regularly reach wide-aligned nose tackles the ultimate find. Falcons head coach Dan Quinn said last week that Mack falls in line with the franchise’s newfound commitment to speed, even at a position that’s not typically associated with wheels. But in deciphering how Mack can excel as a heftier center in this system, Schwartz points to another element of his ex-teammate’s physical makeup. “He’s able to get away with that with his flexibility,” Schwartz says.

Legend has it that Mack — who, again, weighs 311 pounds — can do a split on command. Schwartz says each spring, a new member of Cleveland’s locker room would learn of Mack’s talent and call bullshit. “He’d just bust it out like once a year,” Schwartz says, ‘And you’d just be like, ‘Holy crap, that’s a 300-pounder doing the splits.’”

Amazing as it may be, Mack’s ability to twist his body is more than just a parlor trick. Plenty of centers can reach nose tackles to the play side, but few are expected to handle them alone if the defenders dive behind the play at the snap. “I think that’s kind of the less understood technique in Kyle’s system,” Thomas says. “Most teams, when they have a center, you’re going to have backside help [from a guard].” Mack’s skills as a contortionist allow him to maintain leverage while quickly changing direction and finding his footing. In turn, rather than having to help his center prevent a slanting defensive tackle from blowing up the play, the guard is free to start his pursuit of a linebacker. “That split second the backside guard would take to put his eyes to the center on his first step to protect from a cross face is the difference between [getting to that block and] not being able to get up to that block,” Thomas says.

It’s just one of the small, subtle ways that Mack’s signing has been about more than an upgrade at a single position. A great center is the foundation on which an entire offensive line can be built, and Mack’s presence has rippled through Atlanta’s front in every conceivable way. “You could tell instantly, even in OTAs: This guy knows exactly what he’s doing,” says Atlanta right tackle Ryan Schraeder. “He’s really good at controlling his body, his hand placement — he’s just so thorough about how he goes about his game. That rubs off on everybody.”

Schraeder is able to appreciate Mack’s technical proficiency, but what sticks out to Matthews is how often he’ll look 20 yards past the line of scrimmage and see his center burying a defender in the turf. “One of the coolest things about him is watching him finish,” Matthews says. “He never takes a play off. It’s impressive to see him go downfield and finish guys.”

Matthews immediately felt the steadying hand Mack brought to Atlanta’s offense. Mack wanted to know everything — every blitz, every alignment, every wrinkle that the Falcons could ever see. To help expedite the unit’s collective improvement, Mack has reached out to Thomas when Schraeder or Matthews have questions about a particular technique. It’s a luxury — one made possible by the respect Mack has won from everyone he’s shared a huddle with — and it’s paid major dividends. “[Joe’s] a Hall of Famer,” Schraeder says. “And to be able to get advice like that from him, through Alex, was just really cool.”

As the man in the middle of the Falcons attack, Mack has taken it upon himself to keep everyone playing at the same tempo, and that’s meant tapping every resource at his disposal. “When you really commit to the outside-zone scheme, you’re moving fast,” he said last week. “And you’re moving fast a lot of the time. If you’re not quite used to that, you have to get in shape, and you have to really be committed to, ‘This is the technique we have to use.’ To be successful, everyone has to be on the same page.”

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On the Wednesday before the win over Green Bay, Mack faced reporters assembled at the team facility for a rare standalone moment in front of the camera. “I’m doing a good job by not facing that way,” Mack joked about ignoring the NFC championship game banner behind him. “Not noticing it too much now. [A] press conference is different. I usually don’t do this.” It’s a point that could be interpreted in one of two ways — a podium is an odd place for a center, and for Mack, the quirks of these past few weeks are foreign. He spent seven years in Cleveland without making a trip to the playoffs. A week from Sunday, he’ll play in the Super Bowl.

“We’ve done really well. I don’t think I envisioned quite so well,” Mack says when asked if he thought this type of season was possible when he signed in Atlanta. He’s underselling it. A refined, reliable line has helped the Falcons become one of the most prolific offenses the league has ever seen. Atlanta led the NFL in offensive DVOA, yards per play (6.7), points per drive (3.06), Football Outsiders’ Drive Success Rate, and virtually every other offensive metric. Ryan’s increased comfort in Shanahan’s system, the addition of secondary receiving options like Taylor Gabriel and Mohamed Sanu, and the return of a healthy Tevin Coleman all differentiate this Falcons offense from last year’s version, but no single change has made a more significant impact on Atlanta’s historic output than the offseason signing of Mack.

Thomas and Mack are still close. They’re in touch often, and Thomas says at points during this season Mack expressed to him how rewarding it’s been to play with so much at stake. “What he talked about was how fun it is to be playing for something meaningful at the end of the year,” Thomas says.

The Falcons have helped Mack’s career reach new heights, and he’s done the same for the franchise. It’s no accident that Mack landed in Shanahan’s offense. The deal he got from the Falcons indicated that they understood the type of influence he would bring. “It was so important for Kyle to get Alex in the middle because he knows he’s the best center in football, but he’s also a perfect fit for Kyle’s scheme,” Thomas says. “I think if it was up to Kyle, he would have paid him quarterback money to get him there.”

Mack had to settle for a contract that set the market at his position, and he’s proved he’s worth every penny. Now, to keep up with the Patriots, Atlanta will need plenty more fireworks; Mack is the match that lights the fuse.