On NFL defensive lines, the edge has long been home to the richest guys on the block. Sack totals made stars, and the paychecks doled out to defensive ends went far beyond what interior linemen could imagine. That is, until now.

Over the past few seasons, the delineations between positions and perceived value along defensive fronts have begun to blur. J.J. Watt, the league’s preeminent “defensive end,” has spent a huge chunk of his snaps lining up where a defensive tackle typically would. Part of Michael Bennett’s incalculable contribution to the Seahawks has been his ability to light guards on fire when he moves inside. A never-ending search for mismatches has led defensive coordinators to push their ends toward the ball, and in doing so, they’ve caused the disparity — in both price tag and prestige — between edge rushers and their interior linemates to shrink.

In June, Eagles defensive tackle Fletcher Cox, who remains relatively anonymous to fans outside of Philadelphia and outside a certain sphere of line-play weirdness, got a six-year, $102.6 million contract extension with $63.3 million in practical guarantees. The deal represented the second-biggest annual salary ($17.1 million) among defensive linemen in the NFL. Only Ndamukong Suh earns more annually at $19.1 million, and Cox’s contract included more guaranteed money.

For the second straight spring (Suh signed with Miami in March 2015), the megadeal of the offseason belonged to an interior defensive presence. That changed when Von Miller inked a six-year, $114.5 million extension from the Broncos in mid-July, but even then, the growing uniformity in deals for interior and edge rushers played a role. Miller’s camp reportedly sought a guarantee structure that resembled Cox’s.

Somehow, the interior of the line has become the hottest real estate on the market. There’s a chance this recent string of contracts — Suh’s especially — is the product of situational leverage, a blip in the league that only disrupts the established order temporarily. But given the way the NFL has shifted, and given the players set to follow this crop of newly rich tackles, the interior lineman’s moment in the spotlight could just be beginning.

Any noteworthy era for a position has to start with talent. Even a perfect storm of factors isn’t enough to spark a movement without the right players, and with this group, there’s enough suddenness, power, and bad intentions to go around. From 2000 to 2009 — the year before Ndamukong Suh and Gerald McCoy were drafted — there were 21 instances in which a defensive tackle tallied at least 8.5 sacks. Since 2010, there have been 17.

The mid-2000s were the final gasp for the NFL’s last great group of interior quarterback crushers. Hall of Fame defensive tackle John Randle was 33 years old in 2001 when he piled up 11 sacks in the first season of his late-career stint with the Seahawks. Warren Sapp was 33 in 2006 when he had 10 sacks for the Raiders after failing to top five in any of the previous three years.

Between the turn of the century and the 2010 draft, three defensive tackles went in the top five of the draft: Florida’s Gerard Warren in ’01, Kentucky’s Dewayne Robertson in ’03, and LSU’s Glenn Dorsey in ’08. All wildly undershot expectations. Coming out of Nebraska in 2010, though, Suh was considered a different species. Anyone who watched the Big 12 title game in 2009 had to laugh when the man Suh treated like a chew toy that night — Texas QB Colt McCoy — finished 330 points ahead of him in the Heisman Trophy voting. The former Cornhuskers star finished fourth, but many considered him the best player in college football, and the Lions took him second in the following spring’s draft. One pick later, the Buccaneers snapped up Oklahoma’s Gerald McCoy, considered only incrementally less dominant than his conference counterpart.

Suh’s impact was immediate. He registered 10 sacks as a rookie, the first double-digit sack season by a player who spent a majority of his time at tackle in four years. And according to Football Outsiders’ Total Pressure metric — a look at sacks, hits, and quarterback hurries — he finished 26th in the league and second among interior linemen. Nagging injuries hampered McCoy in his first two professional seasons, but by his third, he was a Pro Bowler. The centerpiece of the Tampa Bay pass rush has at least 8.5 sacks in each of the past three years, and in 2013 no tackle had more QB knockdowns (combined sacks and hits).

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The 2010 draft also featured Geno Atkins, who received far less adulation than his superstar classmates. At 6-foot-1 and with 32-inch arms, he was labeled “undersized” from the start. The Bengals took him in the fourth round, and in his second season, Atkins finished with 7.5 sacks.

In recent years, linemen with Atkins’s profile — short players who have great quickness and a history of college production — have found success on NFL defenses. The Titans’ 6-foot-1 Jurrell Casey is not built like a typical pass-rushing force, but he had 11 tackles for loss in his junior season at USC. Tennessee took him in the third round of the 2011 draft, and he’s comfortably been the Titans’ best defensive player since. The Rams’ Aaron Donald fell to no. 13 in the 2014 draft because he’s 6-foot-1. That seemed stupid then and even stupider now.

An uptick in leaguewide passing has helped “undersized” tackles go from marginalized to empowered, and it’s allowed an entire crop of players we might have never met 10 years ago to become superstars. The Suh-McCoy pairing may be a talent bubble, but the rest of this Golden Age has been made possible because the game has changed — and coaches have done what they’ve had to do to change with it.

In last year’s playoffs, Von Miller went from loving almost mythical creatures to actually becoming one. For much of last season, though, he wasn’t the only dominant force along Denver’s defensive front. Tackle Malik Jackson was an essential part of the league’s best defense. He entered the NFL as a fifth-round pick in 2012 who fell somewhere between positions, but in the Broncos’ scheme, he emerged as an ideal interior rusher too quick for most guards to handle.

Some balked at this spring’s free-agent bidding war for Jackson, which resulted in the Jaguars offering him a six-year, $85.5 million deal with $42 million in guarantees. And while it may seem strange that a guy who’s never had more than six sacks in a season is worth $14.3 million annually, for NFL franchises trying to slow modern offenses, the calculation boils down to basic math.

Above is an image from January’s AFC championship game, just before a snap on a third down in the third quarter. Jackson is lined up in the B gap on the defense’s left side, between nos. 69 and 61 for the Patriots. Miller is more than an entire gap farther outside, head up on no. 88, tight end Scott Chandler.

The distance between the hash marks is 18 feet and six inches. Jackson is positioned about 10 feet from where the ball is being snapped. Miller is all the way on the far hash, about eight additional feet outside. After taking the shotgun snap, Tom Brady will retreat three yards, ending his drop about eight yards behind the original line of scrimmage. By busting out the Pythagorean theorem — which I think I still know how to use — we find that the shortest distance to Brady is four feet shorter for Jackson (26 feet) than it is for Miller (30 feet). That may not seem like much, but working within the time frame of a standard NFL dropback, it can make all the difference.

As ESPN’s Sheil Kapadia wrote after last season’s playoffs, quarterback release times continue to go down every year. In 2012, only seven QBs got rid of the ball in an average of 2.5 seconds or less. Last year, 20 did. Information processing among passers has improved for plenty of reasons, but one cause is the proliferation of the shotgun formation over the past decade. According to Football Outsiders’ data, NFL offenses ran plays out of the shotgun on only 20 percent of snaps in 2006. Last season, 61.7 percent of plays came out of the shotgun or the pistol. That’s a seismic shift. Without having to drop back (as much), quarterbacks can more quickly diagnose the field and uncork throws.

Few do that faster than Brady, who ranked second in the league last season by getting rid of the ball in an average of 2.26 seconds. For Miller to get from his starting point on this play to the place where Brady finishes his drop, the Denver star has to travel 30 feet, or 10 yards. At the 2011 NFL combine, Miller — who is from another dimension — ran the 10-yard dash in 1.57 seconds. That means he has in the neighborhood of 0.7 seconds of wiggle room to get to Brady, and unlike during the combine, he has pads on and a 300-pounder trying to stop him.

Because his joints are made of the green shit used to build Gumby, Miller can often close that gap, but an increasing number of edge rushers cannot. That’s where the four-foot advantage Jackson starts with comes in handy. Even when edge rushers do everything right, they often don’t stand a chance to annoy the quarterback. Interior linemen have become pivotal to a successful pass rush, and more than ever before that’s being reflected in them getting paid at a premium.

Atkins was taken three rounds and more than 100 picks later than both Suh and McCoy, but over the past few seasons, he’s arguably been more valuable to the Bengals than any other interior lineman has to his respective defense.

In 2012, when Atkins compiled 12.5 sacks and was a Defensive Player of the Year candidate, Cincinnati finished with the fifth-best overall pressure rate in the NFL, according to Football Outsiders. After totaling six sacks in just nine games the following year, Atkins tore the ACL in his right knee; the Bengals dropped all the way to 28th in the same category. The following season, with their star still working back to health (he had three sacks in 16 games), the Bengals finished dead last. To the joy of line-play lovers everywhere, Atkins returned to his dominant ways in 2015, and what do you know, Cincy’s rush was back; the team jumped to ninth in overall pressure rate.

Some might attribute the Bengals’ quarterback-demolishing resurgence to defensive end Carlos Dunlap’s career-high 13.5 sacks in 2015, but Atkins’s impact transcends his numbers. The heightened importance of interior rushers leads to heightened attention paid to them, and as Cincinnati’s first sack of last season makes clear, few get more of it than Atkins. By devoting just a single hand to help his guard block Atkins, Raiders offensive tackle Austin Howard lets Dunlap around the edge. Score a sack for Dunlap; score nothing for Atkins.

Following his monster 2012 season, Atkins got a five-year, $53.3 million extension. At the time, it came close to setting the market for interior linemen; only Suh ($12.9 million) and the Ravens’ Haloti Ngata ($12.1 million) had higher annual salaries. That was less than three years ago, and already Atkins has slipped to sixth in that category among players at his position. Even when accounting for a $22 million increase in the salary cap over that time, Atkins still appears underpaid relative to his peers. His $10.7 million average represented 8 percent of the cap in 2014 (the first year the extension kicked in). Jackson’s deal with the Jags, which carries a yearly average of $14.3 million, makes up 9.2 percent of the $155.3 million cap this season. And Cox’s $17.1 million average annual salary is more than Watt, the Rams’ Robert Quinn, and the Giants’ Olivier Vernon will make on average over the course of their deals.

Which brings us to Aaron Donald. The 6-foot-1, 285-pounder could become an unrestricted free agent in 2018, and there’s a chance his eventual contract represents the high-water mark of this entire trend. He has the talent to become the fullest realization of the interior rusher era. No other player can cover the distance between the line of scrimmage and the quarterback faster than he can. Donald has 20 sacks in his first two seasons; no defensive tackle in NFL history has more than 31 sacks in his first three.

At a time when size is giving way to speed, Donald could challenge Watt for the title of Best Defensive Player Alive. When talks about Donald’s new deal begin in earnest — likely after next season — there’s a chance that the league environment will be such that the Rams have to hand him the biggest contract ever given to a defensive player. That environment will only exist because of what he and others at his position did to create it.

The Rams are the perfect case study for just how much the line paradigm has changed. When they signed Quinn to a four-year, $57 million deal with $41.2 million guaranteed in 2014, they paid him like the crown jewel of a pass rush, and with good reason. He was coming off a 19-sack season and looked poised to become the league’s next great defensive end. But on more and more plays (like this one last November against the Bears), it’s clear that even players of Quinn’s caliber can’t bother quarterbacks on most plays.

Offenses are doing all they can to scheme the league’s Robert Quinns into irrelevance, but players like Donald — or, more accurately, the lesser humans who somewhat resemble him — are set up too far inside to eliminate by virtue of dropback distance and release time. The only way to stop Donald is to block him, and good luck with that.