Packers’ Davante Adams is put on a stretcher after being hit in the head during a game against the Bears last September. (Matt Ludtke/Associated Press)

ORLANDO — NFL leaders put the final piece of their just-announced new safety rule in place by saying Wednesday they expect instant replay to be used to help determine whether a player should be ejected from a game for lowering his head to use his helmet to deliver a hit. Even while the final version of the rule continues to be formulated, those within the sport began trying to figure out just how much effect the new restriction on hitting technique will have on NFL playing fields beginning this fall.

“I think we’ll see it have a great effect on one element of this helmet [issue] in how we want the game to be played,” New Orleans Saints Coach Sean Payton said. “I think you’ll still see the physicality. This is the one posture [that’s affected] — we’ll remove it.”

The NFL announced Tuesday it had ratified the rule, which is to result in a 15-yard penalty and a possible ejection whenever a player lowers his head to initiate contact with an opponent. League officials were quick to say it’s not a targeting rule, given that it is not focused on whether a hit targets an opponent’s head. Rather, they said, it is broader, focusing on the technique used by the player delivering the hit to remove a potentially dangerous approach for both the player delivering the hit and the player receiving it.

“Our focus is how to take the head out of the game and make sure that we’re using the helmet as protection and it’s not being used as a weapon,” NFL Commissioner Roger Goodell said as the annual league meeting concluded Wednesday. “That’s the core of what we’re focused on.”

Some players immediately expressed concern that the game is being changed too dramatically.

Washington Redskins safety D.J. Swearinger wrote on Twitter: “Obviously Not Football ANYMORE! THE GAME WE LOVE IS GETTING DESTROYED EVERYDAY.”

Goodell said he’s hopeful that players will be more accepting of the rule once they learn the details of it and the reasoning behind it.

“You’re reacting to players who have not yet heard that dialogue, heard the basis of why we came to where we came,” Goodell said. “And I understand that. But … our intent is to make sure we go in, we go to each team, and we have data, we have the analysis and work that’s been done … to be able to communicate that to them, and give them an opportunity first to understand what the play is before we make a lot of judgments about the ramifications.”

Said Atlanta Falcons President Rich McKay, the chairman of the competition committee: “We’ve got to put the materials together. We’ve got to show the tape. We’ve got to make sure all of you see it, they see it, and it’s taught the same way at all 32 [teams]. If that happens, I think the players — they’re the best athletes in the world and they’ll conform. Hopefully this becomes a springboard, too: take it all the way down, at all levels [of football] because the head [blows] and the lowering of the head has become too commonplace. And it needs to get out of the game.”

The new helmet-hitting rule comes in addition to the NFL’s defenseless-player rules. Those protect a player in a defenseless posture, such as a quarterback throwing a pass or a receiver making a catch, from being hit in the head or neck area.

The new rule came together quickly Tuesday with little advance notice. The rulemaking competition committee initially had planned to issue a directive to the game officials on the matter as a point of officiating emphasis, rather than enact a formal rule. But as the internal conversations took place Tuesday among league officials, owners, general managers and coaches, the focus shifted to a new rule.

“Everyone really felt like this was a necessary step, something that after really hearing the experts talk that we can clearly identify and point to the officials as to how to see this — and then our ability to confirm it in New York if there is an ejection,” said Payton, a member of the competition committee.

A provision that the league’s officiating department in New York can use a replay review to assist the game officials in determining whether a player is to be ejected from a game under the new standard is not yet part of the rule. But Goodell and others made it clear Wednesday they expect that to be added to the rule, perhaps at the next owners’ meeting in May in Atlanta. It would mark a rare departure from the competition committee’s long-held belief that replay should not be used on a judgment call by the on-field officials.

“If we’re able to have replay to confirm when there’s one of these fouls that we think should be removed from the game that also confirms whether someone should be ejected, I think there’s a great deal more confidence amongst the coaches that it’ll be done consistently and fair,” Goodell said. “And I think it also gives the officials more confidence to be able to make those judgments because they know that there will some type of video input in that. … I actually think that the coaches and the clubs and our officials all collectively feel that is an appropriate thing to do. … We think that’s warranted for safety-related issues.”

The threat of an ejection, reviewable by replay, could put teeth into the new rule.

“It’s like anything else,” Redskins front office executive Doug Williams said. “When something goes wrong, you have to suffer the consequences.”

Players must realize that the rule is for their own good, said Williams, a former Super Bowl-winning quarterback for the Redskins.

“When you look at some of the older guys that played this game and the condition that they’re in now — what it is, it’s to protect some of these guys [current players] from when they get older going through the same thing,” Williams said.

League leaders said Tuesday the rule resulted from studies showing that the lowering of the head while delivering a hit is associated with a higher risk of injury. It is being enacted at a time when the percentage of concussions suffered by players that result from helmet-to-helmet hits is increasing, according to the NFL. It also comes after a 2017 season in which the NFL’s injury data showed an increase in the number of concussions suffered by players over the previous season, and during which Pittsburgh Steelers linebacker Ryan Shazier suffered a serious spinal cord injury while delivering a hit in a December game.

Williams said he does not see players lowering their heads to deliver hits with great regularity. But he does see it occur, he said.

“It’s gonna happen,” he said. “Sometimes it happens accidentally. But at the same time, you’ve got to let them know that this is not gonna be part of the game. … There’s not a lot of guys that do that. But it happens.”

The rule potentially applies not only to a defender hitting an offensive player, but also to a ball carrier initiating contact with a defender and also to a blocker. But much depends on how the rule is enforced. A previous restriction disallowing hits delivered with the crown of the helmet seldom was called in games. Some of those familiar with the deliberations behind this rule said they expect it to be applied mostly in open-field situations in which the lowering of the head is obvious and blatant. They said they expect penalties to be relatively infrequent and ejections to be extremely rare.

“I think it’s pretty clear, the effect we want to have,” New York Giants Coach Pat Shurmur said. “We want to get those plays that we’re all pretty aware of out of the game. We don’t want it to be part of our game. There’ll be education as to what you can and can’t do as a player, and then there’ll be consequences. I think as coaches and as teams, we’ll just coach it and make sure we keep the players safe.”

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