NASHVILLE — Trent Dilfer is pushing now. Dusk has turned to dark in the third spring practice for the high school football team he plans to build into the nation’s best, and his players are tired, their shoulders sagging after a long night. They want to go, but he won’t let them.

Lipscomb Academy won only three games over the past two years, and everything Dilfer has heard in the five months since he surprised everyone — including himself — by moving from Austin to be the coach here is that the team kept falling two yards short. So he places the ball on the 2-yard line and asks the offense to line up against the defense and run the ball into the end zone. “It’s just two yards,” he tells the players.

But this isn’t about two yards on a dusty field. It’s about will. It’s about resistance. It’s about reaching deep to find unknown reservoirs of strength that will keep them going when all they want is to give in to exhaustion. It’s about drowning out the voices that say they shouldn’t push too hard or the excuses that sit a finger tap away on the phones stashed in their lockers. It’s about the ball, the goal line and the abyss in between. It’s about everything Trent Dilfer is going to teach them these next few years.

“Two yards!” he shouts.

The Lipscomb players crash into each other again and again, fighting over the end zone. They do this 29 times until finally Dilfer’s offensive line coach, Bruce Kittle, the father of San Francisco 49ers tight end George Kittle, says: “Coach, we’ve got to stop. They’re done.”

Dilfer nods. He pulls off his sweat-soaked cap. And it’s hard to know who is more drained: the players who just ran 29 plays from the 2-yard line or the coach who asked them to do it.

Six months ago, Dilfer had never heard of Lipscomb Academy. He almost scoffed in January when friend and former Seattle Seahawks teammate Matt Hasselbeck first contacted him, on behalf of an acquaintance, about the job. Why would he want to leave Texas to be a high school football coach at a small Christian academy in Tennessee?

But it had been 18 years since he won the Super Bowl as the Baltimore Ravens quarterback and two since he was fired from his job as a TV analyst for ESPN. He was almost 47 and nagged by the sensation he wasn’t doing anything meaningful with his life. The Lipscomb people told him they wanted to build something big, and impulsively he said yes. He wants to make Lipscomb — which has 1,200 students ranging from kindergarten to 12th grade and is affiliated with the university of the same name — the most important high school football program in the country, where the best prospects want to play and state championship trophies sit on shelves.

And yet he is obsessed with something else, too. The hurting that never goes away, bringing tears to his eyes when he talks about his only son, who died 16 years ago, or the career that never matched the promise of being the sixth pick in the 1994 NFL draft. He looks back and sees more interceptions than touchdowns, battles with former coaches and strained relationships in his television life, and he knows that sometimes he was too intense, too pious, too sure he had to be right.

“I think what this is, is pain repurposed into passion,” Dilfer says. “The pain of all my knucklehead mistakes has been channeled into not letting others make those same mistakes.”

He has stormed into his new job much the way he prepared for games as a player — with a blazing drive to do it all at once. His days start before dawn and don’t end until after midnight, and with his wife, Cassandra, and youngest daughter staying in Austin until the end of the year, he crashes with two of his assistant coaches in a mansion owned by a friend of his pastor that’s next door to singer Sheryl Crow’s house. His phone buzzes constantly, its calendar filled with more appointments than he can keep. He wants to invent a new offense and new ways of thinking.

By fall he would like a staff of 30 assistant coaches. Already, he has brought in a group that includes Kittle, a 60-year-old attorney, philosopher and theologian from Iowa who used to coach at Oklahoma, and Trenton Kirklin, a 27-year-old offensive coordinator from Hutto, Tex., whom Dilfer sees as the “next Sean McVay type.”

The whiteboards in his office are covered with scribbles that are each the beginnings of something big. Across the top of one he has scrawled “Boots On The Ground” to remind himself to ask what these huge ideas will look like in real life.

Will it work?

“Do you think I’m just doing high school football here?” he asks. “If it was just high school football, I’d be a crazy man. I’d be a lunatic if this was just to win games. It’s taking 20 hours a day because I’m trying to boil the ocean!”

In the months after his ESPN firing, Dilfer lived the kind of life many middle-aged men dream about. He spent his days playing golf and following his three daughters’ high school and college volleyball games. He had a view of Lake Austin and a wall of flat screen televisions to watch every NFL game at once. ESPN was paying him a fortune not to work, and his few commitments included radio appearances, the occasional investment meeting and 40 days a year with the Elite 11 high school quarterback competition.

Then one Sunday in October, he sat in his church and was overcome with the realization that he wasn’t doing anything significant. He felt disgusted, as if the years after football had been a waste. Who was he helping? Whose life was he making better?

“There was no nobility in my television life,” he says. “There was nothing purposeful in it. It was all ambition and financially driven, and that’s okay but that’s not who I was. That’s not what I wanted to become. I didn’t want to become a 47-year-old man whose career didn’t have impact.”

He also knows that maybe he wouldn’t be doing this if not for Trevin.

Trevin was Dilfer’s only son, the little, 5-year-old blond-haired boy with the mischievous giggle who scampered about the Seahawks’ locker room, hopping into laundry carts and begging wide receiver Bobby Engram to push him around. The players loved him so much he almost felt like one of their own.

But on a family trip a few weeks after the 2002 season, Trevin caught what everyone thought was a cold, except the cold never got better. They went to the doctor, where Trevin’s heart stopped, attacked by an infection. Doctors started his heart again, but the next 40 days were a blur of drives to the hospital, prayers and bedside vigils. On April 27, 2003, with doctors saying there was no longer any hope, Trent and Cassandra removed Trevin from life support.

Dilfer coped by hiding, slumping through the family’s winter home outside Fresno and at the golf course where he knew nobody could find him. He was “numb,” he says. He stopped rehabilitating the Achilles’ tendon he tore near the end of the previous season. He got fat. At night he couldn’t sleep, so he would sit alone in the darkness, sipping wine to make himself drowsy. One glass became two, which became three, then four, then five. Teammates called, but he ignored them. He didn’t care.

Finally, one Friday evening late that spring, he phoned Hasselbeck and said he was done with football.

They had never been close. Hasselbeck didn’t trust Dilfer, who had picked the Seahawks after the Ravens let him go following the Super Bowl win. Dilfer thought Hasselbeck had sulked after Dilfer won the starting job during the 2001 season. But on that night, Hasselbeck could hear the hurt in Dilfer’s voice. He thought about the way Dilfer had always been the Seahawks’ true leader, the voice the players listened to most.

“We need you,” Hasselbeck blurted.

All these years later, Dilfer says those three words are among the best that have ever been said to him. It was like a fever broke. He found he loved talking about Trevin, telling teammates about when the boy carved his initials into the family’s expensive new dining room table or climbed to the top of their rainbow play set before leaping off and shouting, “Trevin to the rescue!” And he came back to football because it was what he had always known and he could see how the game could save someone from the brink of despair.

Sometimes Dilfer looks at his Lipscomb players and wonders what he has missed these past 16 years. He adores his daughters and has thrown himself into their sports lives, but he never got to raise a boy. He never had the Little League practices, the afternoons spent playing ball in the yard, the Friday night pizza parties, the first date, the first car, the first broken leg.

He agonizes about each of his players — even the ones he knows will never play, making sure he is spending as much time on that boy as he would someone who will eventually star in college. What if he was Trevin’s buddy, he thinks. Wouldn’t he want every bit of coaching, every life lesson that Trevin’s father had to give?

“It’s a cheesy way of us getting to see what it feels like, right?” Dilfer says. “I think that’s part of it. It’s not the part, but it’s a part of it.”

Years ago, Dilfer taught Steve Young’s son to throw a football. It might be one of his most satisfying accomplishments. Imagine him, Trent Dilfer, a player with a 70.2 lifetime passer rating for five teams over 13 years, teaching the child of a Hall of Fame quarterback to throw.

But Dilfer’s imperfection as a player made him a brilliant teacher in retirement. He worked hard to be an average NFL passer. Young never had to think about how he threw the ball. He just threw it.

“I know how to teach you how to throw it,” he says. “I know how to teach you better than anyone else how to do it. I know how to get you to tackle a guy better than most people. Not only do I know it, I know how to communicate it.”

He hates these words that are spilling from his mouth, so sanctimonious and self-indulgent. And yet as narcissistic as it sounds, Dilfer also knows he is right. This is what former coaches and teammates and friends have been telling him for years. Trent, you have a gift. You should coach. Finally, he has acknowledged that they were right.

“I don’t mean to sound arrogant at all; it’s almost burdensome,” he says. “I just know that’s what my gift is. That’s what I did on TV. I can communicate to the grandma, the 12-year-olds, the reporter and the gambler.”

At first he was angry when ESPN let him go, but now he sees it as a blessing. And 11 years of confusion are roaring out in these 20-hour days of building a football power.

“I think this is the passion that’s been sequestered for a while,” Dilfer says. “I was passionate about my kids. There was purpose there — but professional passion, I think it’s all just kind of coming out now.”

He wears his Super Bowl ring, which he hates and says feels big and ridiculous on his finger, because he wants his players to have a daily reminder of the state championships he wants them to win. He ditched the team’s colors after seeing research that, other than the Lakers and LSU, most champions who wore gold were from middle schools, and now Lipscomb wears black and purple with a mustang logo that looks curiously like a Baltimore Raven.

“I’m going to show you how to grow up,” Dilfer often tells his young assistants, and in addition to the countless nights spent talking football in the mansion, he has found time to offer Kirklin life advice. One day, at a Lipscomb basketball game, Dilfer pointed to a woman who worked at the school and told Kirklin he should ask her out. Kirklin did, and now he and the woman are about to be engaged. Dilfer is helping him get a ring.

The night after their 29 plays from the 2-yard line, Lipscomb practices again. Dilfer has been watching film of the spring’s first sessions, and the players have improved a lot over three days. He seems happy, almost relaxed.

Suddenly, one of Lipscomb’s wide receivers falls to the ground, shouting, “My knee!” It’s a 15-year-old named Preston, one of the smallest players on the team. Dilfer had recruited him just weeks before, after watching him steal a base in a baseball game. The boy had never played football, but Dilfer loved his fight. He called him “Little P.”

But now Little P is lying on the grass, his knee almost certainly ripped apart in just his fourth football practice. The drill moves downfield, but Dilfer stays behind, resting on one knee, his hand on Little P’s chest, trying to calm the boy staring frightened into the darkening sky. Two minutes pass. Then three and four and five. The trainer hurries to get an air cast and a cart. Dilfer’s hand never leaves Little P’s chest. He prays. He smiles. He tells Little P that everything will be okay and shows him the scar from the Achilles’ tendon he tore in Dallas on the day Emmitt Smith broke the NFL’s career rushing record.

After the cart takes Little P to the locker room, Dilfer leaves practice to check on him. His eyes moisten when he hears Little P has torn his ACL. Later, he will feel guilt for having convinced Little P to come out for football. But he knows, too, that Little P will be stronger because of this, that life’s true triumphs come from the biggest setbacks. And who better to teach that to Little P than Trent Dilfer?

He steps from the locker room and gazes at the field before him, now glowing in the overhead lights. He can see Kirklin coaching the perfect slant route and Kittle’s linemen blocking better than they had the night before and a team that is growing with each practice. He takes a huge gulp of Tennessee air and walks toward the lights, ready to boil the ocean once more.

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