Is the Oklahoma drill a rite of passage or everything to fear about football?

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LIKE EVERY OTHER football player on the night before practice starts, Blake Bell is far too anxious to sleep. It's a humid summer night almost exactly a year ago, and Bell is kept awake by the impending thunderclap of pads. After three seasons at quarterback for Oklahoma, including eight starts in 2013, the 6-foot-6, 259-pound Wichita native has converted to tight end for his final season. For years, he was protected from any contact in practice, but no longer. Bell remembers the night well: lying in bed, unable to escape the thought that in a few hours his future would be determined by a rare event -- a senior making his first attempt at the Oklahoma drill, a simple yet savage hitting exercise that signals the dawning of each new football season.

The root of Bell's night terrors is the telltale sign of the Oklahoma: tackling dummies laid down lengthwise on the field to create a narrow alleyway no more than two yards wide. When called out by coaches, three players -- a defender, a blocker and a ball carrier -- must override the alarms of danger and doubt screaming inside their heads and step into the gauntlet, framed by a frenetic mosh pit of teammates. The task is simple: hit faster, hit harder, conquer. The ball carrier crouches in the backfield as his blocker squats and puts his fist in the dirt. Across from him, the defender does the same. A split second of calm passes as the crowns of their helmets nearly touch. The whistle wails. The players explode into each other like runaway trains. Helmets crack. Joints grind. Feral groans and whimpers escape involuntarily. The back looks for a sliver of space, then tries to pile-drive his way to daylight. When one side has asserted its will, usually in just a few seconds, it's over. As Bill Belichick says, the power of the Oklahoma is the way it quickly answers the most essential questions in football: "Who is a man? Who's tough? Who's going to hit somebody?"

"There's only one way through: straight forward or straight back," Bell says. "That makes it a moment of truth, a do-or-die thing, for every player."

Especially here in Norman, where the Oklahoma drill was invented some seven decades ago. Since then, it has spread and grown to become an annual rite of passage for players. It's one part time-honored tradition, one part skill-building exercise, one part utterly insane, head-on car crash. And there's nothing like it anywhere else in sports, which might be a good thing. In the post-concussion era, the Oklahoma encapsulates the psychological push and pull of the game -- a secretly thrilling and at times sickening three-second snapshot of everything we love and now fear about football.

With practice looming the next morning, Bell sits up in bed and grabs his phone. He knows exactly whom to call. In the late 1970s, his father, Mark Bell, was a fast, snarling, contact-craving tight end and defensive end at Colorado State and for five seasons in the NFL with the Seahawks and Colts. Coaches at Colorado State used the Oklahoma as a kind of human cockfight, pitting Mark against his hard-charging twin brother, Mike, a defensive end, to pump everyone up for the true beginning of the season, the first day of hitting in practice. The brothers didn't mind. They loved that the drill was less about technique or talent and more about measuring the willingness to fight.

Thirty years after Mark last stepped into the fire, he knew immediately what the call from his son was about. No two words evoke more pain and pride in former players than Oklahoma and drill. Even before saying hello, Mark, with a twinge of nostalgia in his voice, summed up the drill the best way he knew how.

"Time to get your mean on, son."

AT 8:30 THE next morning, Barry Switzer, dressed in golf shorts and a light blue T-shirt, steps out of his home on the edge of OU's campus and strolls down the shady side of Chautauqua Avenue toward the football practice fields. Spry and feisty at 77, the Hall of Fame coach, one of only three men to win a national championship and a Super Bowl, never misses the first day of contact. By the time he arrives, the scorching prairie sun has already cooked the wet, thick grass into something that feels like a microwaved sponge. Switzer, though, snarls at the first person who offers him a bit of relief. "No shade," he says out of the corner of his mouth. "Oklahoma drill day. Suck it up."

The tradition dates back to 1947, when Bud Wilkinson took over the Sooners. Before coaching, Wilkinson had served in the Navy's V-5 preflight program, which trained and evaluated cadets for aviation and used boxing and wrestling as tools to weed out pilots who lacked the competitiveness and aggression for warfare. With World War II over and the GI Bill still in effect, Oklahoma's campus -- and football tryouts -- was flooded with former soldiers. Wilkinson realized he too needed a way to assess the "fighting will" of hundreds of potential players.

Wilkinson also wanted something that would train players for his new defense. Most teams at the time were using the wide-tackle six, a heavy, human-barricade-style front. But Wilkinson had developed a way to add speed, athleticism and creativity by positioning his outside linebackers on the line as defensive ends. This was the 5-2 Okie front, known today as the 3-4 defense. To make it work, Wilkinson needed three interior down linemen who could do the work of four (or more) by exploding off the snap, reading the ball carrier and then, in tight quarters, shedding blocks to make tackles. In other words, he needed players who would excel at the Oklahoma drill.

"We just called it the 'one-on-one,' and, oh, I couldn't begin to count the number of times Bud made us run that drill," says Jack Santee, a member of the Sooners' first national championship team in 1950. "It was a competitive, spirited thing, and it's at the very foundation of what we built at Oklahoma."

Wilkinson constructed a dynasty that won three national titles and, between 1953 and 1957, an unprecedented 47 straight games. All along, curious coaches from around the country descended on Norman to steal the Sooners' secrets. And thus the Oklahoma drill became one of the best examples of copycatting in football. By the time Wilkinson retired in 1963, the drill had spread as far as Green Bay, where Vince Lombardi considered it an essential measure of manhood.

While playing in Arkansas, Switzer ran it from both sides -- as a center and a linebacker for the Razorbacks -- and he employed it generously in his 16-year coaching tenure in Norman, leading the Sooners to three more national titles. "The Oklahoma is one of the few Neanderthal drills that I still believe in," Switzer says. "You learn all you need to know about a player, and you learn it in a hurry."

That was the case with current Oklahoma coach Bob Stoops, who in 1979 was a scrawny true freshman defensive back at Iowa. On his first day of practice, Stoops struggled with the Hawkeyes' fancy spring-loaded tackling dummies and could feel the doubtful eyes of his teammates and coaches bearing down on him as the players lined up for the inaugural Oklahoma drill. When his turn came, Stoops stepped up, charged a large running back at full speed and planted him on his back. By the time his teammates finished mobbing him in celebration, Stoops had been transformed, he says, from self-doubting to dominant. He went on to become a four-year starter at Iowa.

When he took over the Sooners in 1999, Stoops immediately reinstituted the drill. "I still remember that moment as being very important for me as a player," Stoops says. "This is a way to test unknowns. To a degree, it does connect us all. With this drill, you become a part of the group."

Somewhere along the line, though, the price of admission devolved into something far more dangerous than Wilkinson ever intended. According to the 2013 book League of Denial: The NFL, Concussions and the Battle for Truth, in the 1970s the Steelers helped popularize a bloody, gladiator-style form of the Oklahoma they christened The Nutcracker. This head-to-head-collision interpretation became the norm in the NFL. At the 1981 Raiders camp, a rookie from Villanova named Howie Long was left battered, bloody and flat on his back by All-Pro blocker Art Shell. As the Raiders' veterans celebrated over his prostrate body, Long pulled himself to his feet, looked Shell in the eye and said, "Let's do it again." Long lost the drill but won over his teammates.

By the 1990s, however, salary caps and the risk of injury to high-paid athletes made the Oklahoma cost-prohibitive for most NFL teams. There are exceptions: In recent years, the Jaguars, Titans, Bengals and Falcons have been known to periodically dabble in the drill. The 2013 Bengals ran an especially gruesome version that allowed a 10-yard running head start; the drill quickly became a fan favorite. Just days later, coincidentally, the NFL agreed to pay nearly $1 billion to settle the landmark concussion lawsuit brought by former players. Almost overnight, the seductive thrill of watching players collide like rams started to feel like a cringeworthy exercise in macho stupidity.

Yet while the NFL, for the most part, seems to have gotten the message, the Oklahoma remains as popular as ever in college. For every Dartmouth, where a coach like Buddy Teevens has minimized contact in practice, there are dozens of schools, such as Ohio State and LSU, that still run collision-heavy hitting drills. The Oklahoma was one of the first foundation-building drills Jim Harbaugh unpacked in Ann Arbor. And since taking over at Tennessee, Butch Jones has started many practices, including the Vols' recent spring scrimmage in front of 63,000 fans, with the Oklahoma and other hitting drills.

Chris Nowinski, a former Harvard defensive tackle who is now an advocate for player safety and the co-founder of the Sports Legacy Institute, recently received an anonymous cellphone video from a practice at a successful Division I program. At the beginning of the video, players are lined up a reasonable four yards apart. When the camera pans out, though, there's no ball carrier. Then the coach steps in and separates the combatants by several more yards, for no reason other than to increase the collision. The team goes crazy without realizing exactly what it's cheering for. "This is the definition of insanity," Nowinski says.

What's more troubling, however, is that the Oklahoma is still a mainstay among high school and peewee players, who are most vulnerable to brain injuries. Nerve cells in children's brains lack the coating, insulation and protection found in adult brains. This not only makes kids more susceptible to concussions but also makes repeat concussions exponentially more dangerous. Kids also have disproportionately large, heavy heads and weaker necks that, compounded by the weight of a helmet, can hinder the control needed to avoid some concussions. This is why, in 2012, Pop Warner outlawed head-on tackling drills in which players started more than three yards apart.

"These little kids playing football and hitting like they're in the NFL?" says former NFL great Bo Jackson. "Their brains aren't even half-developed, and they're out tackling and getting concussions at 9 and 10 years old. ... And the parents are sitting up in the stands cheering? When this kid is turning 15 or 16 years old, this kid is not going to know his name, he's not going to know how to get home from school."

Yet in the South Carolina football hotbed of Rock Hill (population: 69,000), which has produced 11 NFL draft picks in the past 14 years, including Jadeveon Clowney, fans and families still line the football fields with lawn chairs, grills and coolers every August when the local YMCA youth teams hold Oklahoma Drill Night. The coaches, in fact, like to brag that the reason the fields are so lush is not from the rain but the tears (and at least one tooth) shed by players during the drill.

On one oven-hot August night last year, longtime coach Perry Sutton gathers his players, most of them between 7 and 10, near a whitewashed goalpost for a pre-drill pep talk. Struggling to be heard above a chorus of cicadas and a circling ice cream truck, Sutton reviews the importance of safe tackling by reminding the Sylvia Circle Demons of a high school kid who broke his neck in a similar drill. Although he doesn't mention him by name, it's likely Sutton is referring to Jaleel Gipson, a football player at Farmerville (Louisiana) High School who in 2013 broke a vertebra high in his neck during what coaches say was a routine rep in an Oklahoma-style drill. Gipson was declared brain-dead and died less than a week later after being taken off life support. Bengals tackle Andrew Whitworth, a Louisiana native, paid for Gipson's funeral three months before being subjected to the same drill himself.

"Everybody's better off if nobody does it," Nowinski says. "What we should be doing is rewarding and respecting coaches who say, 'We don't have to destroy each other in order to be men.'"

As the long shadows crawl across the field in Rock Hill, though, the crowd grows as the Demons run through dozens of Oklahoma drills. Some reps are little more than skinny kids in saggy football pants and bobblehead helmets harmlessly bouncing into each other. But very often, the cheering crowd, the hyped-up coaches and the inescapable contact produce the thunderous helmet crunch that has come to symbolize the Oklahoma drill's new rite of passage -- into the debilitating dangers of football.

"You're gonna get lit up," a Demons assistant coach reassures his players as Oklahoma Drill Night ends. "But it will help you become a greater player. Or it will let you know football ain't for you."

FORTY-TWO MINUTES INTO the 2014 Sooners' first practice, Bell is still waiting to find out for himself. Stoops blows his whistle and, without raising his voice, says: "Oklahoma." Players race toward the dummies at midfield; they're teetering on a razor's edge, bouncing into each other, screaming through face masks and nearly coming to blows over matchups. "Oklahoma drill day is a football holiday every player looks forward to all year," says Eric Striker, the Sooners' All-Big 12 linebacker. "Every year somebody shrivels up, somebody blows up."

Bell steps through the crowd and puts his right hand in the dirt. When he looks up, crouched down across from him is linebacker Geneo Grissom, his good friend and a future third-round draft pick of the Patriots. Bell and Grissom exchange a knowing smile. There are no free passes, especially for former quarterbacks. At the whistle, Grissom shoots out low and hard, the crown of his helmet hitting Bell in the throat. The collision, which sounds like a baseball bat hitting a windshield, rocks Bell a bit. Grissom's legs are locked, but Bell keeps churning his feet, grinding away the linebacker's leverage. He stands him up, turns him and drives Grissom over the dummies and several yards into a crowd of stunned teammates. The running back dances through untouched.

After one final, declarative shove, Bell is swarmed with congratulatory chest bumps, high-fives and head-butts. "You're not a quarterback anymore, Blake," yells someone from the crowd. "Now you're a football player." After practice, the giddy new tight end calls his dad with the news. "He was so excited," Mark says. "It sounded like the best thing he had ever done in his life."

It was close to it. Bell would go on to play only 12 games at tight end, collecting 16 catches for 214 yards and four TDs. But after his eye-popping performance at the NFL combine, he was selected in the fourth round of the 2015 NFL draft by the 49ers. With less than a year of experience, Bell transformed himself into the sixth tight end selected. Better still, this July, when he reported for his first day of training camp, his days in the gauntlet were behind him -- along with those sleepless nights. Bell has reached the pinnacle: a level of the game where, finally, he's too valuable to be subjected to the Oklahoma drill.

Additional reporting by Anna Katherine Clemmons