NORMAN, Okla. -- Though it happened nearly two decades ago, Mike Leach claims he can recite, verbatim, the phone conversation during which Bob Stoops offered him the Oklahoma offensive-play-calling job.
"It was really pretty quick; Bob's not exactly a talkative guy, anyway," Leach said before recounting Stoops' pitch: "'Hey Mike, you probably heard I just got the head job at the University of Oklahoma. Would you be interested in being the offensive coordinator? I want to run all that stuff you guys did at Kentucky.'"
And with that, the virus that would debilitate the Big 12's defenses was unleashed.
Leach might have been patient zero, but Stoops was the boat that brought the Air Raid offense to the shores of the Big 12. From there, it spread like a contagion to every corner of the league, and beyond -- eradicating defenses along the way.
After Stoops' stunning retirement last month, Oklahoma is now in the hands of another Leach protégé, infected early with the Air Raid bug.
Stoops' legacy at Oklahoma will include the string of terrifying defenses he forged at the advent of his arrival in Norman.
But his legacy to the Big 12, ironically, figures to be the destruction of defense.
Because, whether it was the trailblazing hire of Leach, the addition of the hurry-up tempo, or even the recruitment of Lincoln Riley back to the league, Stoops was a driving force behind why Big 12 offenses have become so unrelenting. And as rivals have followed his lead, Big 12 offenses have never been more potent.
But, it has come at a cost. The league has made the playoff only once in three years and hasn't won a national title since 2005.
And now, playing defense in the league has seemingly never been more futile.
The first symptoms
Stoops landed the Oklahoma job by being the defensive mastermind, paired with Steve Spurrier's offensive genius that resulted in a national championship at Florida.
The year before Stoops arrived, the Big 12 remained a conference predicated on power rushing and ball control. Nationally, struggling Oklahoma ranked fifth-to-last in passing, as Sooners quarterbacks tossed almost twice as many interceptions (16) as they did touchdowns (9). In fact, from the Big 12, only Texas and Kansas State ranked in the top 50 in the country in passing.
That 1998 season, the most effective passing offense in college football actually hailed from, of all places, Kentucky, where Hal Mumme and Leach dared to throw the ball on almost every play.
"Kentucky didn't have the best people in the league, but they were moving the ball as well as anybody," Stoops said. "So I just knew when we started here, if they could do it at Kentucky, why wouldn't we be able to do it [at Oklahoma]?"
At first, the Air Raid was a shock to the system of a fan base raised on Barry Switzer's triple-option wishbone.
"There was a period of time where the two most wanted guys in the state of Oklahoma were me and Josh Heupel," Leach said. "Me for suggesting that you could throw the ball at Oklahoma and in the Big 12. And Josh Heupel for having the temerity to play quarterback and not be able to run faster than 5 flat."
At the beginning, not all went smoothly behind the scenes.
The bulk of Stoops' staff had come from Kansas State, where Stoops had previously coached before Florida. They, too, were unsure about Leach and the Air Raid.
"Bringing guys from Kansas State and other places, I didn't want a melting pot of other offenses," Stoops said. "If I made any right decision, it was that. We were going to be all-in on what they were doing at Kentucky and Mike."
It didn't take long for the rest of the staff or the fans to be sold.
The Sooners scored 40 points in their first three games of the 1999 season, then took Notre Dame to the wire in South Bend. Oklahoma would finish with a scoring average of almost 36 points per game, almost 10 more than the league average.
"Head coach after head coach will say, 'I'll let you run what you want,' then all of a sudden the bullets start going off and they get involved," Leach said. "I made [Stoops] repeat as often as I could that he said he'd let me run it and not interfere.
"And he never did."
And it spreads
After the Sooners topped the Big 12 in passing and returned to a bowl after a four-year drought, it wasn't long before others attempted to replicate Oklahoma's success utilizing the Air Raid.
After his one year in Norman, Texas Tech hired Leach, and Lubbock became an incubator for the looming outbreak of the Air Raid, both to the Big 12 and other conferences.
There, Leach groomed, among others, Dana Holgorsen, Kliff Kingsbury, Sonny Cumbie, Sonny Dykes, Seth Littrell and Riley, who combined would spread variants of the Air Raid to Oklahoma State, West Virginia, Houston, TCU, Texas A&M, Cal, North Carolina, Arizona, North Texas, Bowling Green, Louisiana Tech, Indiana, East Carolina and, in the case of Riley, whom Leach hired to be an assistant at age 20, back to Norman.
Leach eventually took his offense to Washington State and the Pac-12. Today, even the likes of Ohio State and Clemson have their offenses rooted in the Air Raid.
"I'd love to give you some dramatic response, but I knew it would work," Leach said. "How could it not work? If I thought the offenses other people were running were better, I'd be running that offense. I knew it wasn't better. Somebody might have better players. You might get overpowered. And, obviously, I'm biased. But the material does pretty well bear me out.
"People are copying this offense. Not the other way."
The big mutation
While Leach was successfully cultivating his attack at Tech, Oklahoma's offense under Stoops was only becoming more lethal.
During the 2000 national championship season, in a remarkable stretch the Sooners put up 63, 41 and 31 against No. 11 Texas, No. 2 Kansas State and No. 1 Nebraska, respectively, on their way to an unbeaten season and BCS national championship.
Because of its passing prowess, Oklahoma was becoming a destination for blue-chip quarterback recruits. And with a tradition rooted in Heisman halfbacks and All-American offensive linemen, the Sooners incorporated a bruising rushing attack into Leach's spread formation principles.
"I knew that by bringing [the Leach offense] here, it would attract quarterbacks," Stoops said. "The evolution of it for us, I knew when we brought it here, we would be able to -- being that we were Oklahoma -- put more of a run game with it. And recruit to a run game."
By then, there was no going back. For the rest of the Big 12, it was merely about keeping up.
In 2008, just a decade after owning only two of the nation's top 50 passing offenses, the Big 12 boasted five of the 10 highest-scoring attacks.
And that's when the mutations started.
In 2008, Oklahoma returned one of the nation's top quarterbacks in Sam Bradford, who had just set the FBS freshman record for passing efficiency.
During the previous offseason, Stoops had suggested to then-offensive coordinator Kevin Wilson that the Sooners snap the ball as fast as possible between plays, to give Bradford more opportunities to gash opposing defenses.
"My opinion was: If my quarterback Sam Bradford snapped the ball more than your quarterback, I like my odds," Stoops said. "And even though it was going to affect and would not help our defensive statistics and what we were doing on defense, I still felt the advantage of him directing the offense, the more opportunities he had with the football, the more opportunities we had to win.
"And for the most part, that was pretty true."
There was no antidote for Stoops' latest wrinkle, as the Sooners scored more points than any other offense in modern college football history. They also became the first FBS team in 89 years to put up 60 or more points in five consecutive games, capped with a 62-21 rout of Missouri in the Big 12 title game.
The rest of the league quickly followed suit, and now tempo has become the norm in the Big 12, as well.
As a result, Big 12 defenses are defending an average of 10 additional plays per game more than they did in the late 1990s.
The defenses flatline
If it seems like Stoops and his staff were just mad scientists unaware what this offensive plague would do, they weren't. They were watching its decimation firsthand in practice daily.
"I was willing to sacrifice some of the defense for [the tempo]," Stoops said. "What people don't realize, when you're practicing the tempo, you're not able to make corrections in practice. Other times you would slow it down, correct what you did on defense and get it right. Well, when the tempo is going, you don't have time to. So, there in the end, it doesn't lend itself to that."
When one of college football's top defensive minds like Stoops is willing to sacrifice in the name of offense, it's not difficult to see why the bottom has fallen out on defense in the league.
In 1999, the average ranking for total defense for Big 12 teams was 35th. Two years ago, that ballooned to an all-time-worst 90th. Last season, the Big 12 didn't have a single defense ranked in the top 50. And only Kansas State and West Virginia had defenses in the top 75.
"In the Big 12, it's pressure on you every snap. You screw up defensively and it's six points," said West Virginia defensive coordinator Tony Gibson, who previously coached defensive backs in the Big Ten and the Pac-12. "Oregon was fast-paced, but other than that, you had a pretty good handle.
"In this league, you're going to give up yards. I don't care who you are, or what your scheme is. Any game can turn into a shootout."
The Big 12 surely isn't alone in its problems defending Air Raid-tempo arsenals. Even Alabama's vaunted defense, loaded with future first-rounders, surrendered a combined 75 points in the past two national championship clashes with Clemson.
Yet nowhere has the offense-at-the-expense-of-defense approach taken hold the way it has in the Big 12.
"It's like you play three quarters, and in other leagues, it's the end of the game," Gibson said. "We're playing a game and a half sometimes.
"That is taxing -- mentally, physically."
Is a cure in sight?
As defense has waned as a priority in the Big 12, so, too, has the league's prowess on the national stage.
Because of its style of play, as Stoops first predicted, the Big 12 has thrived recruiting quarterbacks and offensive skill talent. Six of the nation's top 24 quarterback recruits for 2018 have already pledged to join the Big 12.
But for the other side of the ball, the well has gone dry, as elite defensive prospects have shunned the Big 12.
In February, the Big 12 collectively signed only one top-45-ranked defensive tackle and one top-35 defensive end.
"Part of the narrative out there has been, 'There's a lot of scoring, so the defenses must not be great in the Big 12,'" Riley said. "But it may just be that all these offenses in the Big 12 are pretty darn good, and there's not a break every other week like you get in some of these other conferences."
Despite the league's title drought, Stoops also fiercely contests the narrative that this virus has rendered the league incapable of winning a national title.
"That wasn't the narrative in our last couple of Sugar Bowls, correct?" he said, referring to convincing wins over Alabama in 2013 and Auburn last season, which included a pair of strong defensive performances from the Sooners. "What did Oklahoma State do, what was the narrative in their [bowl] this year?" (The Cowboys scored 38 against Colorado, the Pac-12's second-ranked defense.)
"Some people turn a blind eye to it. Or they pick games where it didn't go that way. You can pick whatever games you want to put whatever narrative you want out there."
Narrative or not, what Stoops started with that call to Leach is not changing. Not with the majority of the league running versions of a tempo Air Raid.
That includes Oklahoma, which has undergone yet another offensive renaissance with Riley calling plays. The past two seasons, the Sooners have ranked fourth and third nationally in scoring.
"When I hired Lincoln, I made it very apparent why I wanted to get back into this system," Stoops said. "Little by little, we had drifted away from it.
"But I believe in it."
A belief for which defense has had no cure.