The American, however, is fighting for far more than just personal glory as he aims to spread awareness about mental health -- an issue close to his heart.

In 2015, he was the first responder at the Charleston Church shooting that left nine people dead.  After the tragic incident, he suffered post-traumatic stress disorder; he also had panic attacks and suicidal thoughts.

After struggling for years, Delaney sought help. Finally, therapy and mixed-martial arts training helped him overcome his troubles. The decision to seek help saved him and changed his life forever.

Born in a rural town of just 2,000 inhabitants -- Willow, Alaska -- a career in global MMA promotion seemed like a long shot. The second oldest of four siblings endured bullying and finally found wrestling when he moved to Florida at age 14 when his mother married his stepfather.

While his passion is the grappling arts, his big body made him a perfect candidate for the football team. So, he made a deal with the coaches that he would play football if they started a wrestling program for him.

"I went to high school at South Walton High in the panhandle of Florida -- they didn't even have a wrestling team," Delaney recalled. "In the south of the United States, football is king, and the coach said that he would start up a wrestling program if I played on the line. So, I did."

The young athlete was encouraged by his mother and stepfather to pursue both sports, and along the way he met an influential figure that supported his journey toward state and all-American status in high school.

"I got passionate about wrestling largely due to a man named Maty Chouinard, who had been my mentor since freshman [year] of high school. I think he saw something in me and helped push me along in my wrestling career and my athletics. And honestly, in my development as a man as well," Delaney said. "He would take me all over the country to tournaments, and I think that he really fired that passion inside me, because he believed in me and thought I could be someone special. For a young man, I think it's important to have somebody there that's doing that for you."

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That passion led him to become a four-time Southern Conference Champion and a Citadel Hall of Fame athlete. After college, "The Witness" went into law enforcement for a time before realizing that his talents are better served elsewhere.

"I went through some hard things in law enforcement and kind of had to redefine myself and change my career path," he explained. "Wrestling had always been my thing; [I thought] I'd like to try jiu-jitsu. So I started trying and fell in love with it."

"Some good people said to me that if I'd learn a couple of submissions and got good at jiu-jitsu, I'd be a killer, and if I learned a bit of striking, I'd be a super killer, and then it kind of naturally happened that way for me," Delaney added.

Reinvigorated by the career change, the American Top Team athlete earned a contract to compete in ONE Championship where he aims to deliver his message of hope to everyone watching his matches.

"Just pure career-wise, I want what's best for my family. And I don’t know if anyone is in it for anything but that," he explained. "But I also want to show through fighting that you can be a tough, strong, capable man who can do amazing things, but it's also okay to be vulnerable."

Watch ONE 158 live on NETVERSE, Vidio, Kaskus TV or MAXstream beginning with the lead card at 4:30 p.m. Western Indonesia Time (WIB) on June 3.

The main card broadcasts live on NETVERSE, Vidio, Kaskus TV and MAXstream at 7:30 p.m. WIB. Also, NET TV will air a same-day delay at 10:00 p.m. WIB.

This article was published in collaboration with ONE Championship.