Ken Norton Jr. is in the middle of his first season as the Raiders' defensive coordinator. (USATSI)

When Raiders defensive coordinator Ken Norton Jr. first steps out onto the field, he rolls up one of his pant legs. Before he takes his first sip of water, immediately after unscrewing the cap to the bottle, he sprinkles a few drops onto the ground beneath him. Both are inconspicuous actions, both might go unnoticed. Even if they are noticed, they might be dismissed as a coach's nervous habits.

But they're not meaningless, they're not unplanned, they're not superstitions. They're a tribute to his late father, Ken Norton Sr.

"I always pour my water for my father," Norton Jr. says. "He takes the first drink."

When Norton Jr. first began coaching in the league, after an NFL career that saw him become the first and only player in the history of the game to win three consecutive Super Bowls, he would roll up his left pant leg as a way to get ready to work. The routine puzzled his father, who always asked him about it. Now that Norton Sr. has passed, the purpose of the rolled-up pant leg has changed. Now, he does it to memorialize his father.

"Now I roll it up for him, because I know he's always asking about it," Norton Jr. says. "'What about that pant leg? What about that pant leg?'"

Norton Jr.'s father is best known as the man who broke Muhammad Ali's jaw. But Norton Sr., a former World Boxing Council heavyweight champion, played a much bigger role in his 70 years.

He left college to serve in the Marine Corps. More importantly, he was a father to Norton Jr., raising his son on his own.

That's what sticks the most with Norton Jr. to this day -- not the punches, not the notoriety that came with being Norton Sr.'s son, but his father teaching him how to ride a big wheel, his father cooking for him, his father being there when he cried. Those are the memories that are alive within Norton Jr. today.

"He's always with me," Norton Jr. says. "There's not one day that I come into the office or take the field when I'm not thanking him. There's not one day when I don't have my water and I'm not pouring it out to give it to him first, because everything I do, everything I think, the way I speak, the way I walk, the way I talk, the decisions I make are all extremely influenced by his upbringing of me."

*****

In Norton Sr.'s younger days, he wasn't known for his boxing prowess. Instead, Norton Sr. was an ex-Marine who only joined the military after he got into a spat with his college football coach and his father found him sitting on the couch at home. His father told him that if he wasn't going to college, he had to do something productive, like join the military. So, Norton Sr. became a Marine.

"Once he became a Marine, it really gave him discipline," Norton Jr. says. "It really gave him focus ... It got him to fighting. It really taught him a lot about being a man. And it made him tough -- mentally tough. It changed his life."

It was in the military that Norton Sr. picked up on boxing. But he didn't get his big break professionally until Ali came calling in 1973.

Norton Sr. seized his chance. During the fight, he broke Ali's jaw. When the fight ended after 12 rounds, Norton Sr. was declared the winner via a split decision.

"It's always been an example for me," Norton Jr. says. "You never know when it's your turn. So you have to get ready, stay ready."

That moment not only changed Norton Sr.'s career, but it also changed Norton Jr.'s life. They moved into a new apartment in Southern California. Norton Jr. got a new bike. As he puts it, "a lot of things happened after that fight."

Ken Norton Sr. lands a punch against Muhammad Ali during their title fight in 1973. (Getty Images)

Unfortunately, one aspect never changed: his father's cooking.

"He wasn't a good cook, so we had a lot of cold hot dogs," Norton Jr. says. "He did hard-boiled eggs pretty good. He'd boil things."

Whenever his father had a girlfriend, Norton Jr. always asked if she could cook.

"That was always an important quality," he says.

Of course, Norton Sr. wasn't just a bad cook to Norton Jr.

"He was very caring, he was tough, he was matter of fact," Norton Jr. says. "He was very dependable, very honest. And he was always someone I could always go to and talk to."

Norton Jr. says he didn't fully realize what kind of father he had until he became a father himself.

"Just really love your kids, be there for them," Norton Jr., a father of three, says. "Let them learn, but at the same time teach them. Give them a nice place to live. Learn how to cook ... Make sure they understand the value of hard work and education ... Those things were extremely important to him and, in turn, they're important to me for my kids."

*****

The calls began in 1986. Then a linebacker on the UCLA football team, Norton Jr. first heard that dreaded late-night ring. With his ear to the receiver, Norton Jr. processed the words from the other side of the line.

On the night of Feb. 23, 1986, Norton Sr. crashed his car on an on-ramp to the Santa Monica Freeway. He fractured his skull, jaw and leg. According to The Los Angeles Times, there were no witnesses. He wasn't using drugs or alcohol at the time. No evidence unearthed what actually transpired. He couldn't remember what happened.

Ken Norton Jr. rolls up his pant leg as a tribute to his father. (USATSI)

But Norton Sr. battled back. He wasn't supposed to survive that wreck, Norton Jr. says, but he did. He overcame it.

"He was fearless," Norton Jr. says. "I've never seen anything that he faced that he was afraid of. For me, when things come up, I know my father would've handled it. So it makes it easier for me to handle."

In his later years, Norton Sr. survived a series of strokes. Norton Jr. knew his father's health was slowly deteriorating, still he refused to accept what would eventually happen.

"You could see it happening before your face, but knowing how strong of a man he was, knowing he was my Superman, I don't think you ever really think you'll lose your father," Norton Jr. says. "You see it happening, you hear the doctors, you know what's going on, you've seen people pass before, but not my father. So I don't think it ever really sets in until it actually happens."

On September 18, 2013, Norton Jr., then the Seahawks' linebackers coach, received another one of those calls. His father had passed away at the age of 70 due to congestive heart failure.

"Unless you've lost a parent ... you can't really understand," Norton Jr. says. "It's devastating. It's one of the biggest losses you'll ever have. It changes your life for the worst and for the better. And you never ever get over it. It's something you never ever get over. You think about it daily. It's just a part of your life."

*****

Today, Norton Jr. is in the middle of his first season as a defensive coordinator after spending years as a defensive assistant with Pete Carroll at USC and in Seattle, winning his fourth Super Bowl ring in 2013.

Now, he's running the show in Oakland, where the Raiders are in the thick of the playoff hunt for the first time in forever.

"He always said, I don't care what you do ... but just be the very best at it," Norton Jr. says of his father. "Just go all out with your passion, put your heart into it, and you'll be rewarded."

Norton Sr. has been gone for over two years now, but his son still carries his father with him -- when he's with his family, when he's alone in his office, when he's on the football field, always.

Norton Jr. still pours out his water. He still rolls up that pant leg.