Aaron Donald gives credit to the basement gym in his house growing up for helping him become the player he is today. (4:22)

LOS ANGELES -- Aaron Donald was uncommonly sentimental on the afternoon of Dec. 23. He had just broken the record for sacks by a defensive tackle, accumulating 19.5 with a game remaining, and so he found himself on the verge of tears as he rode the Los Angeles Rams' bus out of State Farm Stadium in Glendale, Arizona, that Sunday. There, Donald crafted long, heartfelt text messages for all of the people who helped mold him into what might now be the greatest, fiercest player in the NFL.

The first one went to his father, Archie Donald, and the first sentence was poignant.

“You created a monster.”

That monster was built in the Lincoln-Lemington-Belmar neighborhood of Pittsburgh, a gritty suburb in the northeast section of the city. It was built in the basement of that unmistakable two-story brick house with the red-and-white awning, in the homemade gymnasium that Aaron began to work out in before sunrise as a high school freshman. It was built, in many ways, by Archie, a former nose tackle and longtime workout junkie who introduced Aaron to strength training as a way to inject structure into his son’s life, igniting the obsession that precipitated greatness.

“A lot of my success, and a lot of who I am now, is because of my dad, and the way he raised me and taught me how to have a work ethic,” Donald told ESPN. “I always tell my dad he was training me to be a pro before he even knew it.”

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Archie grew up in the southern part of Homewood, historically one of the most violent areas of Pittsburgh. He once won a weightlifting competition by bench pressing 405 pounds, and eventually became the subject of folklore for the vicious hits he delivered on the field, some of which allegedly broke helmets. Archie played football up until his freshman year at Norfolk State. He broke his kneecap and never returned.

Years later, his youngest son, Aaron, began to make a name for himself while dominating older kids as a short, stumpy fullback and defensive lineman. But Aaron ate too much and worked too little. He was admittedly “lazy as a kid,” and Archie strove to change that. He lit a fire under Aaron by introducing him to weightlifting at the age of 12. Two years later, Archie ran out of workout partners and summoned Aaron to lift weights with him before work.

Wake-up time was 4:30 a.m. They met in the basement by 4:45 and worked out every muscle group for nearly two hours every weekday morning.

“He was a little lazy about it at first until he started seeing a change in his body,” Archie said. “That’s how it usually works when you’re lifting weights. You don’t like it because it hurts. But when you start seeing a change in your body, then and only then do you start doing it. And at that point, once he started seeing a change in his body, by the time he was coming out of high school -- I mean, man, he was waking me up every morning trying to get a workout.”

Dewayne Brown provides speed-and-agility training for athletes of all ages in the Pittsburgh area and has been working with Donald since he was in high school. Over the past two offseasons, while Donald held out in hopes of a lucrative contract extension, the two spent basically 14 of 24 months together. Donald began his workouts for the 2018 season in late January, only a couple of weeks after his Rams were eliminated by the Atlanta Falcons in the wild-card round of the playoffs.

On the first day, Donald told Brown he hadn’t yet played his best football.

“My eyes shot up,” Brown said. “But I believed him.”

Donald was the 2017 NFL Defensive Player of the Year. He was also named first-team All-Pro for the third consecutive time and registered 11 sacks in 14 games, tying a career high. And yet he swore there was more in him.

“I just knew I could play better,” Donald said. “I could clean things up as far as playing the run a little better, rushing the passer a little better.”

Donald somehow reached another level this season for a Rams team that finished the regular season 13-3 and will play the New England Patriots in the Super Bowl from Atlanta on Sunday (6:30 p.m. ET, CBS). He recorded 20.5 sacks, two shy of the overall record set by Michael Strahan and 2.5 more than the defensive tackle record set by Keith Millard. He tallied 73 pressures, according to NFL Next Gen Stats, more than anyone in the league despite facing an inordinate amount of double- and triple-teams as an interior lineman.

The presence of free-agent defensive lineman Ndamukong Suh was supposed to open everything up, but Los Angeles defensive coordinator Wade Phillips said opposing centers have been shifting over to double Donald on almost every pass-rush snap.

Rams offensive lineman Rodger Saffold doesn’t blame them.

“That would be my plan,” he said. “But if you don’t do it effectively, then he’s going to beat you. Because all he has to do is choose who he wants and then go from there. That quickness is a big part of his game, but it’s the power once he gets there that changes everything.”

Donald was double-teamed on 60.5 percent of his pass-rush snaps, the third-highest rate in the league, according to NFL Next Gen Stats. Still, his pass-rush win rate -- the number of times a player beats blocks within 2.5 seconds -- was an NFL-best 38.8 percent.

Donald became the only All-Pro to garner all 50 votes and is now the third defensive lineman since 1965 to be first-team All-Pro four times in five seasons, joining J.J. Watt and Reggie White. On Saturday, he’ll likely join Watt and Hall of Famer Lawrence Taylor as the only players to win back-to-back Defensive Player of the Year awards.

Some, like Brown, see a man who summoned extra motivation to validate his contract. Others, like Saffold, will tell you Donald has become smarter about anticipating where the help will come from, then beating the guard off the snap before it even arrives. Others notice sheer anger.

Aaron Donald's dad said his son was a little lazy and overweight before he began weightlifting with his father. Courtesy Donald family

“It’s almost like he takes it personal now,” Rams defensive lineman Ethan Westbrooks said.

“He’s playing with an attitude,” Donald’s older brother, Archie Jr., added. “Even though he got that big paycheck, he still plays with a chip on his shoulder.”

Archie’s heart skips a beat every time Aaron calls. They usually communicate through text messages, so the rare phone call triggers apprehension. That feeling swept over Archie on an otherwise lazy morning in late August, when his phone began to ring and Aaron was on the other side. Archie was lying on the couch watching "NFL Total Access" and hearing about all the players signing exorbitant contracts, none of whom included his son.

Then Aaron began to talk.

“Hang up your cleats,” he said. “You’re done.”

“You sure?” Archie asked, already knowing what that meant. “I’ve been waiting my whole life to hear that.”

“Retire,” Aaron told him. “Sit back and watch the games now, old fella, it’s all on me.”

Aaron had just agreed to a six-year, $135 million extension that included $87 million guaranteed and, for a brief moment -- until Khalil Mack signed a slightly larger deal with the Chicago Bears a day later -- made him the highest-paid defensive player in history.

Immediately after agreeing to terms, Aaron called his mom and dad.

“You could hear them crying over the phone,” he said.

Archie grew up without a father and vowed to be an enduring presence in his children’s lives. He ran a commercial cleaning company for a while, but it faded after the Sept. 11, 2001, terror attacks that soured the economy. He later worked in construction, delivered phone books and recycled tires, piecing together odd jobs in order to make ends meet. His ex-wife, Anita Goggins, initially stayed home to care for the couple’s three children and later drove buses.

Aaron and Archie Jr., who is three years older, shared bunk beds as kids, and the thought of someday helping their parents retire was a frequent topic of conversation. Over the years, it evolved into a dream that drove Aaron. It pushed him through the early-morning workouts, sharpened his focus in the wake of persistent double-teams and triggered the aggression that made him unstoppable.

“We sat there together and it brought tears to our eyes, man,” said Archie Jr., a standout linebacker at Toledo who bounced around the NFL as an undrafted free agent before retiring in 2012. “I mean, to be a part of that, to be a part of that call, to be a part of seeing him call his parents, our parents, and tell them, ‘You're done, you don't have to work’ -- that’s something that I always wanted to do, and I got to be a part of it through my little brother.”

When Aaron won Defensive Rookie of the Year in 2014, he surprised his father with a pickup truck. For his 53rd, and most recent, birthday, he bought him a $40,000 Rolex Sky-Dweller watch (Aaron regrets telling Archie the price because he now refuses to wear it). Weeks after he signed the extension, Aaron’s mother and father met with his financial advisor, who presented a portfolio that promised $1 million for each -- with taxes paid off -- and a brand-new home of their choosing.

They both retired immediately, a moment Aaron thought about “a lot” as a kid.

“But it was just a dream,” he said. “You never think that you would have opportunities to do what you’re doing. You always dream things, but I feel like the stuff that I dreamed was small compared to what’s happening now.”

Rams general manager Les Snead sat in his office in Earth City, Missouri, in the lead-up to the 2014 draft watching tape of Donald at the University of Pittsburgh. Kevin Demoff, the chief operating officer, walked in and noted that it was “good point-of-attack film,” which is basically a highlight reel for offensive and defensive linemen.

“No,” Snead told Demoff, “this is just a normal game.”

Concerns about Donald’s height -- he’s listed at 6-foot-1 -- limited him to three scholarship offers coming out of high school and gave him a fifth-round grade after his junior season at Pitt. But he always jumped off the screen, from pee wee football to high school and the Atlantic Coast Conference.

“I say this in every interview, but nobody could ever block him from the first time he put on a helmet and shoulder pads,” Archie said. “There was no way you were going to block that kid. No way.”

Brown, the trainer, first met Donald at a scout camp in the summer before his senior year of high school. Donald forgot his cleats that day and dominated every other kid in sneakers. Five years later, Rams defensive line coach Bill Johnson, at that time coaching for the New Orleans Saints, saw Donald at the Senior Bowl and deemed him “by far the best player on the field.”

Mike Waufle, the Rams defensive line coach at the time, begged his team to pick him.

“I felt like he was the best college player I’d seen, even when I was in college football, at that position,” Waufle said. “A lot of people didn’t like him because he was undersized. I said he’s the best player that I’d seen at that position. I had him on my board higher than Jadeveon Clowney at that time. So, I made a big push.”

Donald became the best defensive player in college football by his senior year at Pittsburgh. Charles LeClaire/USA TODAY Sports

When Donald came to the Rams’ facility as part of a visit, Waufle brought him into the draft room, where Demoff, Snead and former head coach Jeff Fisher were watching film of quarterbacks. Waufle, a former Marine who stands 6-foot-4, crouched slightly and wrapped his arm around his new favorite player.

“I want you guys to meet Aaron Donald,” he said, a big smile on his face.

When the draft began, Waufle muted his TV and buried himself in paperwork. He looked up after the eighth pick, scrolled through the list of names and couldn’t believe Donald wasn’t among them. Four picks later, Waufle snuck back into the draft room.

“You got your guy,” Fisher told him.

“That was pretty cool,” Waufle said of the Rams taking Donald at No. 13 overall.

Shortly after Donald joined the team, Waufle pulled him aside. He told Donald he was going to hear a lot of talk about technique and that he wanted him to ignore all of it. “Just play,” Waufle told Donald. The fundamentals would come later, and the arsenal of pass-rush moves would expand with it. But Waufle didn’t want to bog Donald down with too much, fearing it would dilute his special gifts.

Waufle, who coached at the collegiate and professional levels for nearly 40 years until retiring after the 2017 season, was asked if he ever shared a similar message with another rookie.

“Never even thought about it,” he said. “Ever. Ever, ever. I wouldn’t do that with anybody else.”

Archie moved into the house Aaron bought him last month. His sons never let him sell the old place, which means that basement gym -- “The Dungeon,” as Aaron affectionately calls it -- remains intact. Archie, Archie Jr. and Aaron still work out there in the offseason from time to time. The new home is in Penn Hills, Pennsylvania, a stone’s throw from where Archie Jr. and Aaron attended high school.

On the immediate right of the front door is a framed photo of Aaron in a tuxedo, posing in front of seven collegiate awards after his breakout senior year. In the corner of that wall is the Bronko Nagurski Trophy for the best collegiate defensive player, which Aaron won on Archie’s birthday. Downstairs, in the new basement, lies a scrapbook that contains a perfect juxtaposition.

Donald led the NFL in sacks this season. Joe Robbins/Getty Images

On one page is a photo of a pre-teen Aaron posing on the sand in Virginia Beach, Virginia, using a boogie board to hide his pudgy stomach.

On another page is a photo of Aaron before the homecoming dance during high school, wearing a tight muscle shirt to show off his sculpted physique.

“The before and the after,” Archie said in a hearty laugh. “That’s the transformation right there.”

Archie, who attends all of the Rams’ home games, comforted Aaron through the first three weeks of the season, when the sacks weren’t coming and Aaron was starting to put pressure on himself to live up to his contract. He then watched his son go off, Aaron notching two or more sacks in seven of his next 13 games, a stretch that included 40 quarterback hits and four forced fumbles. His fourth-quarter prowess against the Seattle Seahawks, Minnesota Vikings, Kansas City Chiefs and Detroit Lions basically won games.

“I can’t believe he’s that good,” Archie said when asked what he thinks about when he watches Aaron play. “It’s the honest-to-God truth. I can’t believe he’s that good.”

Aaron’s work ethic has become almost as legendary as his play. Archie Jr. begs him to take vacations every offseason, but he won’t do it. If he messes up a drill during those grueling speed-and-agility sessions, he does it all over again. As a rookie, Aaron used to leave the facility with the rest of the team on Fridays, then would be the only one to come back, staying through the night to analyze tendencies of opposing offensive linemen.

“I would always leave,” Snead said, “and his car was always there.”

The determination stemmed from Archie’s workouts, though Archie is uncomfortable accepting credit.

“I just led him to the water,” he said. “It’s all Aaron now at this point.”

Aaron echoes that sentiment often. He made that point to his parents when he informed them that they could retire, and he did it again after breaking Millard’s record four months later, in the final sentence of the drawn-out text message that he sent to Archie.

“I work hard to make you and mommy millionaires,” Aaron wrote. “The best is yet to come.”