RALEIGH — As firsts go, it isn’t much of one, particularly for Andrew Wallace. The N.C. State right tackle became the first ACC player to have to sit out a play for losing his helmet when his lid popped off during the Wolfpack’s opener against Tennessee.

Wallace was far from the last, thanks to a controversial new rule that has college coaches concerned. A player whose helmet comes off not only must stop participating in that play, but has to sit out the next play unless the helmet came off as a result of a penalty.

“I can see the safety behind it,” Wallace said. “Having to come out the next play, that’s a little too much. Maybe just the rule that you have to stop if your helmet comes off. Then you put it back on, and that’s it.”

Both players and coaches say they understand the player-safety implications of a player blocking and tackling without a helmet, and there are no complaints over the intent of the rule, which is to prevent concussions and other serious head injuries.

It’s the one-play banishment that has raised objections over the implementation of the rule, particularly when the penalty paid can be as stiff as losing a quarterback or pass-rushing defensive end for a vitally important play, or even losing a game on a 10-second runoff in the final minute.

If that part of the rule was designed to encourage players to strap on their helmets more tightly, it hasn’t worked so far.

“I would like to see that revisited after the season. I hope that we do that,” Duke coach David Cutcliffe said. “We shouldn’t be having to take a quarterback out in the last minute of the game. You can’t even take a timeout and get the guy back in. … There are problems with it. It wasn’t very well thought through.”

In Clemson’s opening game against Auburn, quarterback Tajh Boyd lost his helmet because of a perfectly legal play by the defender: he put Boyd in a headlock and twisted his helmet off like a bottle cap as he tackled him. As long as the defender doesn’t grab a helmet opening or facemask, it’s not a penalty, so Boyd had to leave the game and Clemson lost its star quarterback for a play in the middle of a drive.

That kind of play raises fears among coaches that the rule will end up having an unintended negative impact on player safety. If opponents start deliberately trying to remove helmets, particularly in the final minute when a lost helmet could end a game prematurely, problems could arise.

“If a helmet is coming off, it has to be seen by an official, someone grabbing the facemask or intentionally ripping it off,” Virginia coach Mike London said. “I have yet to see penalties thrown where someone was intentionally trying to grab a helmet off through a facemask or through just trying to rip it off. But you’re seeing more helmets come off.”

In Saturday’s game between North Carolina and East Carolina, there were at least seven helmet violations, more than twice the national average. According to the ACC, its officials called 115 helmet violations in 32 games, with only three penalties for a player continuing to participate.

That pace, of 3.6 violations per game, is consistent with rates nationally. It has also remained consistent through all four weeks of the season so far, which suggests that players either haven’t adjusted yet or there’s nothing they can do about it.

Wallace switched to a different model of helmet before the Wolfpack’s second game, against Connecticut, then lost it again. He now has his helmet cranked down so hard it gives him headaches. Duke linebacker David Helton, who has a self-described “weird-shaped head,” hasn’t found a helmet yet that fits perfectly. He’s struggled to keep his helmet on throughout his football career.

“(The new rule) didn’t scare me too much,” Helton said. “I just make sure if it does come off, I put it back on real quick.”

DeCock: (919) 829-8947, luke.decock@newsobserver.com