Dartmouth football coach Buddy Teevens hasn’t let his players tackle each other in practice for five years.

Yes, he has been called crazy. Of course, he hears from skeptics who don’t understand how he can build toughness and technique that way. But Dartmouth’s reduced injury rate and success on the field, coupled with 37 years in coaching, tells Teevens it’s common sense to not tackle at practice.

“You look at some of the concussion data that comes out, it’s targeted in August and March,” Teevens said. “Why? Spring and fall practice. That's concussion season. The game is special. Either we change the way we coach the game, or we won’t have a game to coach.”

The Ivy League made a dramatic change last week when its coaches decided to eliminate full-contact hitting from regular-season practices, as first reported by The New York Times. It’s the most extraordinary step taken so far in college football to try to combat growing concerns of long-term brain injuries due to head trauma -- and it’s a smart move.

Whether people want to accept evolution or not, this is the future for all of football. Every level of college football is now on the clock. The same is true for high school and youth football, where it's smarter for younger kids to play flag football in order to protect their more vulnerable brains.

If the Ivy League says no tackling at practices, why are those concepts not best for Alabama, Ohio State and Oklahoma players? That’s the question now directly staring in the face of college football coaches and leaders and they have nowhere to duck.

The NFL allows only 14 full-contact practices during the 18-week regular season. The players negotiated this through collective bargaining. The NCAA guidelines -- they're not rules -- state that live contact should be limited to twice a week at practices during the regular season. That's a standard the Ivy League initially set in 2011 before its latest change.

The NFL tackling limit is "essentially what we’ve done in the Big 12,” said Big 12 commissioner Bob Bowlsby, chairman of the NCAA Football Oversight Committee. “We voluntarily put ourselves below the limit nationally. I don’t think our guys missed a beat on it. Whether or not they’d be willing to take the step the Ivy took, I don’t know.”

Bowlsby said more information is needed from a joint concussion study currently being conducted by the NCAA and Department of Defense.

“I think we have to be thoughtful about (making changes),” Bowlsby said. “We know there are implications for concussive events. We don’t know very much about what the implications are for subconcussive repetitive use for blows to the head. Until we get some data on it, it’s going to be hard to make an informed decision.”

It wasn't hard for the Ivy League. Teevens said it was about a five-minute conversation among Ivy League coaches last week. The rules still allow contact by wrapping up and making thud hits with players staying on their feet. What’s different is no more tackling players to the ground, said Robin Harris, Ivy League executive director. A formal proposal is still being adopted to get passed by athletic directors in May.

“I do think we’ll see this at all levels,” Harris said. “I don’t know how long it will take. Research and data take a long time to develop. We can’t wait for the research. As research comes in and we need to modify something, we will. Frankly, what I don’t understand is why everybody doesn’t adopt the same tackling rule in one fell swoop. Then no one is at a competitive disadvantage and we protect the athletes.”

Keep in mind, the NCAA doesn’t have safety rules, it has guidelines for hitting and concussion protocol. (The Ivy League has safety rules that could be enforced if needed but discipline hasn’t been necessary, Harris said.) Outside of twice-a-week tackling in the regular season, NCAA guidelines permit live contact four times a week in the preseason and eight out of 15 spring practices (with a limit of two per week and not on consecutive days).

A recent article on NCAA.com said that based on new helmet-sensor data, there is a general consensus on how to limit football contact during the preseason and “other high-risk practice periods, including the spring.” The article said updated guidelines are “several months away” and must be endorsed by several medical and coaching associations.

As radical as no tackling at practice may sound, a lot of this is common sense. Many coaches are already scaling back on full contact. The more players hit, the more chances their brains get knocked around. Some doctors believe repetitive subconcussive hits are the biggest danger. Those hits may not lead to symptoms or a diagnosis that cause a player to leave a game or practice.

Head trauma has been associated with chronic traumatic encephalopathy (CTE), a debilitating brain disease. In 2014, the NCAA’s own lawyers signed off on a proposed settlement in which experts for the plaintiffs determined college football players are three times more likely than the general population to have symptoms related to CTE.

“What we’re finding in concussion data is that in addition to head-to-head risks, it’s also hitting the ground that’s a danger,” Harris said.

Before you blow this off as Ivy League mumbo-jumbo, consider the background of Teevens, Dartmouth’s coach. He has coached at Florida, Stanford, Tulane and Illinois. He worked under Steve Spurrier with the Gators and regularly got advice from Bill Walsh at Stanford. Teevens is a football lifer who has coached at the highest levels.

Up until 2010, Teevens was like most coaches and conducted standard practices with full contact, including live scrimmages, one-on-one drills and goal-line situations. When the issue of concussions started gaining steam, Teevens learned from St. Louis Rams coach Jeff Fisher that he doesn’t have players tackle in the preseason anymore. If it could work in the NFL, Teevens thought, why couldn’t it work at college?

“I just told my coaching staff, ‘We’re not going to tackle anymore.’ They’re like, ‘OK, what’s the punch line?’” Teevens said. “Look, I’ve gotten challenged on our toughness with what we do. My attitude is you won’t make a guy get tougher with hitting at practice. I think you can improve his tackling technique and assignment. I have guys that have become very capable tacklers who are not the toughest guys on the football team. Why? They practice it a lot more.”

Teevens said Dartmouth’s injuries of all kind dropped significantly without live tackling. He said the team had two concussions last season (both on offense) and missed tackles decreased by 50 percent after the tackling change occurred.

Last season, Dartmouth started using a “mobile virtual player” for tackling in practice. It’s a remote-controlled dummy that moves throughout the field and mimics routes taken by live players. Stationary pads are also used to practice tackling.

“We actually tackle more than most people in the country; we just don’t tackle each other,” Teevens said. “That’s one thing I tell my recruits: If you come here, you’ll never be tackled by a teammate or tackle a teammate. We tackle 10 games a year and we do a pretty good job at it.”

Dartmouth won a share of the Ivy League title in 2015, its first conference crown since 1996. Dartmouth’s defense led the Football Championship Subdivision in scoring and yards per play allowed. Teevens recently had an exit interview with linebacker Will McNamara and asked his team captain what he thought of no tackling at practice.

“He said, ‘Coach, I’m calling bull(expletive) on that,’” Teevens said. “‘I didn’t buy into it the first year and after that I felt better than I ever did in high school.’ He led the league in tackling. He’s convinced this made us better. I ask my coaches point blank if you go someplace else, would you do what we did here? To a man, they said this is the way to go.”

The evolution of football doesn’t need to be viewed negatively. If anything, this is the Ivy League’s push to preserve football, the sport it launched at universities in the late 1800s and protected in the early 1900s when players were dying on the field.

History is now repeating itself. This time, players aren’t dying on the field; some of them are dying years later as their brains fail them. Parents are watching. They’re thinking twice about letting their kids play football.

Once again, the Ivy League is leading a path to the game’s future, whether college football's multibillion-dollar industry accepts this inevitable conclusion now or in a couple years.

“Hopefully, the higher levels of college football take a page out of our playbook,” Teevens said. “The end result is their long-term health is safer. I feel better about myself knowing I’m not putting a guy in jeopardy and I’m not jeopardizing our chance to win.”

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Dartmouth uses mobile virtual players to reduce full-contact tackling. (Dartmouth/YouTube)
Dartmouth uses mobile virtual players to reduce full-contact tackling. (Dartmouth/YouTube)