Imagine an NFL player who has been perfect for almost 12 seasons; a man who has been true every moment of his career – never once sliding in the mud or stumbling to catch his feet or enduring a bad day. It seems impossible. Even machines occasionally break down and humans err.

Dallas Cowboys long snapper LP Ladouceur does not.

You may have never heard of Ladouceur though he has played for more than a decade on one of the world’s most famous teams. Chances are you wouldn’t recognize him without his helmet since the majority of his television appearances are closeups of his backside in the instant before he flicks a football between his legs. You have, undoubtedly, seen his work in the form of a decade’s worth of precise snaps whistling true to Dallas punters or flying toward the hands of holders on extra points and field goals. It is highly unlikely you took a moment to marvel at his reliability.

Long snappers live to be ignored because if they are noticed, it usually means a calamity has occurred. A snap has been botched and the ball is flying over the punter’s head or rolling helplessly toward the holder on a field goal, throwing the game’s most anonymous player under the glare of the television lens. Suddenly everybody knows the long snapper and there’s no place to hide. For Ladouceur, his perfection is silence.

“I think the more you play this game, you start to realize that mentally you have to be sharp,” he says by phone following a recent practice. “The physical part is kind of a given. The guys who last long know that.”

Long snappers are often everybody’s joke; the guy at the bottom of the roster who has little to do with the result of the game. They are derided for their lack of impact, unappreciated by fans who have no idea the mental toll of waiting alone until the time comes to snap the ball. A few years ago, the Madden video game ranked Washington long snapper Ethan Albright as the league’s worst player, as if they knew something about him. He was a snapper and snappers have failed at more demanding positions, the thinking goes.

Nobody understands the importance of a long snapper until something happens, which is the damning thing about precision at the position. Last Sunday the Philadelphia Eagles lost their long snapper, Jon Dorenbos, to a season-ending wrist injury. Then Brent Celek, the only other Eagle who could long snap, injured his neck and couldn’t play. This left Philadelphia without a snapper. They couldn’t punt or kick field goals, until late in the game when, in desperation, they brought out tight end Trey Burton, who was able to complete an ugly, awkward snap on a go-ahead field goal. Two days later, they signed a real snapper to replace Dorenbos.

At least the Cowboys understand the value of a reliable snapper. They have bestowed on Ladouceur two, five-year contracts over the years which is almost unheard of for a NFL player. His career earnings approach $10m and he has carved a life for himself in the Fort Worth suburb of Aledo that no football-loving kid from Montreal could have dreamed of living. All for roughly seven snaps a game.

But if you think any of this is easy, it is not. Technique is important and while fans may scoff, long snappers put in long hours of practice on top of gym sessions and team meetings. Ladouceur says he works with the kickers and punters for large chunks of each Cowboys workout constantly bending over and snapping. Again and again and again until he has it right.

“Basically [a snapper has] to be a linebacker, but backward, be able to snap the ball backward like the quarterback throws,” Cowboys special teams coach Rich Bisaccia once told the Ft. Worth Star-Telegram.

But it’s hard to be a linebacker who isn’t really a linebacker. In college, Ladoceur was a defensive lineman and he still keeps the defensive player’s longing to run downfield and hit somebody. He has seven career tackles but rarely gets to make contact on punts or kicks. He lives in a strange dynamic inside the Cowboys locker room, playing a position that should give him a bond with offensive linemen but knowing he can never live in that closed society, while remaining an outsider as well to the defensive linemen who would normally be his peer group. He is friends with players in both groups but he is a special teams player, a designation that puts him in a different realm.

LP LaDouceur: ‘The physical part is kind of a given. The guys who last long know that.’ Photograph: Icon Sports Wire/Corbis via Getty Images

Still, he has played long enough to build a certain respect and has plenty of friends on the team. He has lived more Cowboys history than almost any other active player other than quarterback Tony Romo, who dropped a perfect snap from Ladouceur on what should have been a game-winning field goal in a 2007 playoff game against Seattle.

Logic says Ladouceur shouldn’t be here. Kids from French-speaking Canada rarely find their way to the NFL. But Ladouceur loved football and he was a relentless linebacker and defensive lineman at Notre Dame High School in Montreal, then later at nearby John Abbot College. He drew scholarship offers from several American colleges including Syracuse, California and Michigan State, choosing Cal after falling in love with the school on his official visit. He imagined a career as a dominating defensive lineman, but after a knee injury and a coaching change, he fell out of the defensive line rotation.

There was, however, an opportunity for a long snapper. And at some point he realized that any hope of playing professionally rested with his ability to snap efficiently on kicks. After graduating with a degree in earth and planetary sciences he was sighed by the New Orleans Saints who kept him through training camp, cutting him just before the final preseason game. He left New Orleans on one of the last flights before Hurricane Katrina arrived, returning to California where he waited in Sacramento for another shot at the NFL.

It came a few weeks later in the most surprising of ways. Because of a scheduling quirk, the Cowboys had games in San Francisco and Oakland on consecutive weekends and decided to spend the days in-between practicing in nearby San Jose. During the trip, they released their snapper and started looking for a new one. A Dallas player who shared the same agent as Ladouceur alerted the agent who put in a call. An invitation was extended and Ladouceur drove that night to the team hotel. The next morning he stepped into a team van headed to practice only to find the team’s omnipotent coach Bill Parcells and owner Jerry Jones a row in front of him.

“I was a Cal guy, I had long, blond hair” Ladouceur recalls with a laugh.

“We know about you,” Parcells said to him that day.

And all Ladouceur could think was: “What have I gotten myself into?”

But he survived. He nailed his snaps in that first game and then the others that followed. After the season, the Cowboys gave him a one-year contract and then another and soon he was the player whose roster spot was never questioned. “It’s definitely been a blessing,” says Ladouceur. “Every day I think about Coach Parcells saying yes. I saw him a couple years ago at the hall of fame game and I thanked him”

Parcells gave way to Wade Phillips who gave way to Jason Garrett and still Ladouceur remained. There’s never a need for a good long snapper until you need him.

He built a life in Dallas. He got married and started a family. He and a friend went into business as contractors building new houses. He loved the idea of putting families in houses. He became something of a name in an area where the Cowboys are the most powerful cultural institution. The long snapper who never made a mistake. When he retires he wants to teach French at his neighborhood high school.

“I feel like I’ve cemented myself,” he says. Before his thoughts turn towards teaching: “I feel I can do something great there.”

And yet there are few guarantees when you are the last player on the roster. Perfection has kept him with the Cowboys for all these years but somebody is always watching: waiting for hints of complacency, waiting to see if there will be failure.

On the very afternoon Ladouceur talked with the Guardian about his life as a snapper, a coach had observed Ladouceur in practice, noticed one snap was slightly off and noted the moment.

“A little high on the first one,” the coach said at the end of the workout.

A little high? After 12 years of perfection?

Ladoueur chuckles. “You can’t get too comfortable,” he says.

Nobody sleeps on perfect.