Back when Baron Corbin was on the Arizona Cardinals’ practice squad — long before he became the man the NXT Universe loved to hate — he had a reputation as a bit of a loose cannon. If an opposing player pulled a dirty move or stepped out of line, Corbin had no problem putting them in his place.

“One time, I was practicing against the Tennessee Titans, and one of their defensive linemen took a cheap shot at our running back, so I planted him,” he told WWE.com. “When he got up, he tried to get in my face. My [offensive] line coach shouted that he had a better chance of winning the lottery than that fight.”

It’s that kind of supreme confidence, along with three Golden Gloves boxing titles and several grappling championships, that makes Corbin one of the most dangerous men in NXT. He has demolished nearly everyone in his path in mere seconds, cementing his reputation as a no-nonsense a**kicker.

Now, The Lone Wolf has met his first true test in Samoa Joe, whom he’ll face at the historic NXT TakeOver at the sold-out Barclays Center in Brooklyn, N.Y. Though Corbin has come into his own as a brawler since arriving in NXT, his showdown with Joe is the fight he’s been waiting for his entire life.

TakeOver preview: Baron Corbin vs. Samoa Joe

Corbin can’t recall a time when he wasn’t scrapping with someone, starting at a young age.

“I have a brother, we had some good brawls,” he recalled. “Our dad was an iron worker, a really tough guy. He raised us to be strong and stand up for ourselves. Whatever we want, we go and get it. Sometimes, you have to take it.”

With a strong competitive nature, he took to the gridiron as a fourth grader to get his fill of physicality.

“You find out what you’re made of at a young age,” Corbin explained of his early football days. “When you get knocked down, you figure out if you want to be the hammer or the nail. I wanted to be the hammer.”

The Lone Wolf adapted his aggression to the football field as he grew up, settling in as an offensive lineman. Though many kids dream of tossing the perfect pass or breaking off a lightning-quick rushing play, Corbin lived for the collisions that came with every snap.

“Everybody always asked why I wanted to be an offensive lineman,” he said. “I told them that I had 11 different people I can hit on every single play, while everyone else is chasing one person. I prided myself on being an extremely physical and dominant player.”

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That dominance carried the 6-foot-8 Corbin throughout his football career. He was an All-American at Northwest Missouri State, where he made a routine of winning awards for the biggest hits of the game, along with the rings he proudly shows off for capturing four conference championships.

But Corbin wasn’t satisfied with the full-contact melees on the football field. He started boxing in high school and went on to become a three-time Golden Gloves champion. He took up grappling, jiu-jitsu and mixed martial arts, and won various full contact tournaments.  He kept on fighting, which proved to be a positive for him as he made it to the NFL. Though many see football as a metaphor for war, the fight was very real for Corbin, who battled on a daily basis for a spot on the Arizona Cardinals roster, sometimes coming to blows with other players.

“You’re fighting for a job, for food on your table,” Corbin said. “Everybody else there was competition. They were trying to take from me what I wanted. There were definitely some days at training camp that I got in fistfights. I stood my ground and did what I needed to do to keep my job.”

Surprisingly, Corbin’s reputation for fighting didn’t get him kicked out of any locker rooms. Instead, coaches and players stood behind him. When he was signed to the Cardinals’ practice squad, he sometimes found himself with time off when the team traveled. Not content to sit around, Corbin dove headfirst into MMA training, learning more and more about different ways to inflict pain.

“There are a lot of different facets to it,” he explained. “There’s ground game, grappling, jiu-jitsu, kicking, punching, elbows. You have to be prepared. You have to learn how not to panic in certain situations. It requires a lot of thinking.”

According to Corbin, everything he fought for in football, boxing and MMA has been for one reason. “I did all of those things to get here and do the most destruction that I could walking in the door,” he stated.

Since his NXT debut in Sept. 2014, he has done just that. At first, the NXT Universe gravitated to the quietly charismatic Lone Wolf, counting the seconds it took for him to dismantle another opponent. Yet as time wore on and independent wrestling stars – such as Finn Bálor and Sami Zayn, with flashy moves and theatric entrances – took over NXT, fans began to turn on Corbin as he racked up win after win with little more than his devastating End of Days. Laser-focused on succeeding in WWE, Corbin doesn’t care whether he has support or not.

Watch Corbin's impactful NXT debut

“I’m not here for them, I’m here for me,” he declared. “I’m here to make a name for myself, and I’m going to get it done any way that I can.”

The arrival of independent standouts in NXT leaves a sour taste in Corbin’s mouth as well. He feels that they’re taking opportunities from him, which may as well put a huge target on their backs.

“I look at these guys that come in with a name, but it’s on the internet,” Corbin said. “It’s someone’s opinion. It’s created with these fan bases of people who are diehards and watched them with 12 or 15 people in a high school gym. They’re nobodies. I’m the real deal. The NFL, boxing, jiu-jitsu, I did that. I’m proven at what I can do.”

The Lone Wolf sees himself as the latest in a long line of football players who made the transition to the squared circle and wreaked havoc, including WWE Hall of Famer Ernie Ladd, Wahoo McDaniel and Goldberg, to name a few.

“We’re a**kickers,” Corbin stated simply.

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Corbin has met one of his first true tests in Samoa Joe. The submission specialist surprised the NXT Universe — and Corbin — when he put The Lone Wolf to sleep with the Coquina Clutch.

“I have a little respect for Joe,” Corbin said. “But I had just beat up two guys. He’s a veteran and knows how to take an opportunity. He got in a lucky sleeper hold.”

Corbin vows that Samoa Joe won’t be so fortunate when they face off again at TakeOver: Brooklyn. He’s out to prove a point to all of his doubters.

“I’ve only used what I needed to in order to win,” Corbin said. “Now, I can go deeper into my arsenal. Samoa Joe doesn’t know what’s coming.”

That’s how Baron Corbin likes it. The aggressive NXT Superstar’s mantra can be boiled down to the words that he recently had inked into his flesh on WWE Network:I am the agent that decides your fate.

“That means I’m in control. You have no choice in what happens,” he said.

“If you’re in my way, you’re done.”

Watch Baron Corbin vs. Samoa Joe this Saturday at NXT TakeOver, only on WWE Network