If you have a thing for irony, consider the current role of Daniel Lee Jesus Fluker. A starting offensive tackle for the San Diego Chargers, Fluker goes by “D.J.” and he is essential security detail for the team’s quarterback, Philip Rivers. The 6-foot-5, 340-pound Fluker clogs the arteries to Rivers with remarkable effect. The Chargers are currently 5-2, largely because of the soaring excellence of Rivers, who, often untouched by the opposition, recently became the first NFL quarterback to post four straight games with a passer rating of 120 or better.

While Fluker’s current job is to protect Rivers, it was an unprotected river that marked the defining moment of his severe childhood that put him on a path of displacement, destitution and devastation.

For all the natural disasters that come without warning, Hurricane Katrina’s reputation preceded her arrival. In August 2005, residents of New Orleans knew a storm was coming. That included the Fluker family: D.J, his mother, two sisters and brother had left town and taken refuge in nearby Biloxi, Miss., when the storm hit. They were safe, but when the muddy Mississippi breached its banks, the Flukers’ modest home in the Lower Ninth Ward was destroyed. Without insurance or their possessions, they were suddenly consigned to living in their Ford Escort, all five of them. D.J. was 14 at the time and already weighed close to 400 pounds.

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Often homeless and penniless, the family pinballed across the Delta, to Mississippi to Alabama to New Orleans in search of stability. “We struggled and struggled and struggled some more,” Fluker recalls. “We went church to church, shelter to shelter. Sometimes we couldn't do that so we would sleep in the car.”

D.J. remembers nights when the family would have no food and would eat out of the garbage dumpsters at fast food restaurants. Other times, he says, he and his siblings would wear pants smelling of urine because they had nowhere to wash their clothes.

When D.J. was attending McGill-Toolen High in Mobile, Ala., the students held a fund drive for a family in need. Reckoning that this family must be even worse off than his, D.J. scrounged up a $1 to donate. The Flukers, though, were the recipient family. That same year, the McGill-Toolen coach offered to let D.J. sleep in a spare bedroom, as the family’s daughter had gone off to college. D.J. was filled with emotion. “I’ve never slept in a bed by myself before,” he explained. He was 15 years old.

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By then, Fluker was establishing himself as a football player of some distinction. (He would be one of more than 100,000 homeless kids playing for a high school or college in the U.S.) But all the displacement and transferring schools and the absence of structure took a toll on his academics. And as much as he liked learning, he felt the need to get a job and offset some of the expenses that included his food bill. Time he could have devoted to studying was devoted instead to mowing yards, building piers and cleaning out sheds. Minimum wage was better than no wage.

By the time he graduated from high school in Foley, Ala., Fluker earned a football scholarship to the University of Alabama. He learned many things in college. For one, after holding his own against his teammates and then against the best players, he came to see himself as a future NFL player. “I had coaches that kept telling me. ‘You can be somebody,’” he says. “That was so motivating.”

He realized that there was no shame in his homelessness and that plenty of teammates -- including the Crimson Tide’s star running back, Trent Richardson -- survived similarly brutal childhoods. He also had an awakening as a student, taking advantage of tutoring and graduating in three-and-a-half years with a degree in health science. By then, he was an All-America and a member of three BCS National Championship teams.

There was one minor scandal while Fluker was playing for Alabama. His name surfaced in a report, naming players who accepted under-the-table payments from agents. What gifts did Fluker lavish on himself with this impermissible cash? He bought a bed. And he paid for a plane ticket so his girlfriend could watch his final college game. (That season, Alabama football program reported more than $100 million in revenue.)

The Chargers selected Fluker with the 11th pick in the 2013 NFL draft. His contract included a $6.6 million signing bonus. One of his first moves was to buy his mom a home in Mobile. It was hardly a mansion. But it was spacious and sturdy. And it ensured that no Flukers would be sleeping in a sedan or a church basement. One of his next moves was pay tuition so his younger brother Leon could attend college.

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By the time Fluker arrived in San Diego, he’d completed an almost unfathomable journey. He was on the West Coast, thousands of geographic miles -- and immeasurable cultural miles -- from the Delta. He had sudden wealth, almost beyond his comprehension. He would be playing professional football, enjoying all the trappings that came with it, from first-class travel to the services of a team nutritionist. “There are so many times when I say to myself, ‘I can't believe you’ve come so far.’ I feel like I worked hard; I’ve always taken pride in that," he said. "But it’s like, if I knew what was ahead, I would have worked even harder, you know?’”

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Especially now -- at a time when the U.S. homeless population is at a record-high -- Fluker is often asked what advice he gives to kids enduring the hardships that framed his childhood. He doesn't want to minimize the struggle with rosy optimism. But he tries to impress a message of hope. “Have faith in God. Have faith that you can overcome," he says. "There were days when I said, ‘I got two legs, two arms, I can see. I have a purpose.’ … Stay in school. Every day when you wake in the morning, say ‘I can keep pushing and I can get what I want.’ Just hang in there. Trust me, it's possible. I’m proof, I guess.”

Still, there are plenty of reminders of his struggle. He and teammate Ryan Mathews, a running back, bonded while commiserating over their childhood homelessness. (As an infant, Mathews spent months living out of a 1969 Oldsmobile with his mother.) In training camp, Fluker revealed that -- because of a fear of water that intensified after Hurricane Katrina -- he never learned to swim. So it was Manti Te’o, another rookie (though 100 pounds lighter) who accompanied Fluker to the team pool and gave him swimming lessons.

Fluker will not be giving up his status as one of the NFL’s best linemen to try out for the Olympic swim team. But, as ever, he persevered. “Put it this way,” says Fluker. “I’m not sinking any more.”