Donte Jackson is so fast, it's illegal.

No, really: He’s so fast that his top speed breaks the law.

Jackson is best known for his skills on the football field as a starting cornerback at LSU. But he’s also one of the best sprinters on the school's track and field team, competing in the 100 and 4x100-meter relay.

This spring at the SEC Relays, Jackson ran a personal-best 10.22 seconds in the 100, which puts him moving at an average of almost 22 mph.

The speed limit on LSU’s campus is 20 mph.

The LSU Police Department did not comment on whether it intends to bring Jackson to justice. But even if it wanted to, it would have to catch him first.

Good luck with that.

“When healthy, I’m way over anybody that plays football when it comes to running,” Jackson said. “Not healthy, some guys might stand a chance.”

In the spring, Jackson claimed the unofficial title of “fastest man in football” thanks to that 100 time, which as of March was the fastest wind-legal score of any Football Bowl Subdivision athlete by two-tenths of a second. Jackson lost his crown a few months later when Alabama’s Tony Brown, who doubles as a defensive back for the Crimson Tide, ran the 100 in 10.12 seconds at the NCAA outdoor championships.

But that isn’t slowing down Jackson’s self-confidence. In his mind, Jackson knows he’s the fastest player in the game, and he’s willing to prove it as often as he needs to.

Since he was young, Jackson has known his speed was “on a different level” than everybody around him.

At Riverdale High School in New Orleans, he won Class 4A state championships in the 100 and 200 meters as a senior. During the recruiting process, he posted the fastest 40-yard dash time at an Alabama camp, clocking in at 4.42 seconds.

Now at LSU, he could be the track team’s top sprinter this spring, after the departures of Nethaneel Mitchell-Blake (now a world champion after he helped Great Britain to gold in the 4x100-meter relay in August) and Tremayne Acy.

The scariest part is, Jackson doesn’t think he has reached his full potential. And neither does anyone else.

“The only negative I had about Donte coming out of high school was I don’t think anybody ever knew what his true 100 percent was,” said Brett Bonnaffons, Jackson’s coach at Riverdale. “His 85 percent was so much better than everybody else. I was waiting to see what his 100 percent was.”

By continuing to push himself, Jackson believes he can break the 10-second mark in the 100. He was quick to note his personal best was set when he wasn’t 100 percent healthy.

A sub-10-second time not only would put him tops among college football players, it would be one of the fastest times in the country (and the world) this year. By comparison, Tennessee's Christian Coleman set an NCAA record with a time of 9.82 this season; that remains the world's fastest wind-legal time in 2017.

“I feel like I can go faster than what I’ve showed or what my times say,” Jackson said. “They probably have a guy who clocked a faster 100 time than me, but I still feel like they aren't faster than me until they beat me.”

To hit his goal, Jackson works with a former “fastest man in football,” LSU sprints coach Bennie Brazell, who was the first Tiger to win national championships in two sports — as a member of the 2003 football team as well as the 2002 outdoor and 2004 indoor track and field teams.

LSU has a long history of fastest-in-football claims, including Brazell, his former teammate Xavier Carter and later Trindon Holliday. For now, Jackson is the third-fastest of that group; he's behind Carter and Holliday, who posted 10-second times as career bests.

The football and track programs share a close relationship that encourages players to compete in both sports. The football team has three players who also spend time in track, and coach Ed Orgeron said he wishes more would join.

“You bring that physical nature from football over to the track and have that mental toughness aspect,” Brazell said. “(Jackson) likes to compete. Football players and guys that do two sports with track just have that in them.”

But there’s only so much hard work can do. Jackson mainly credits his speed to genetics and God-given talent. He's the second of five siblings, including an older brother who played college football and a younger sister who runs track at Southeastern Louisiana.

Jackson grew up competing with his siblings in everything from foot races to making the best eggs. An environment like that helped cultivate Jackson’s abilities, pushing him to the limit of what he could do — an attitude still prevalent today.

Jackson believes no one is faster than he is, and he’s not going to stop until there’s no doubt in anyone’s mind.

“We were very competitive in everything in we do,” said Jackson’s sister Aareion, the SLU track standout. “My mom had to stop us from competing. It was always a competitive household. I still think I could beat Donte, but he’s afraid to race me.”

Donte rolled his eyes at his sister’s challenge.

“She’s not ready yet," he said. "I try to tell her that, but she doesn’t know.”

Follow Mike Gegenheimer on Twitter, @Mike_Gegs.