The veteran fighter has battled drug addiction, demons and himself in the past. In 2006, Riggs and Nick Diaz infamously continued their UFC 57 fight at the hospital afterwards with Riggs firing punches undeterred by the IV in his arm.
Eight years to the day since his last UFC bout, the 32-year-old Riggs returns to the Octagon to face welterweight Ben (Killa B) Saunders on a televised UFC Fight Night card Saturday in Phoenix.
"I'm really excited, I'm ready to fight, man. I'm in the best shape of my life and I'm going to knock it out, for sure," Riggs said in an interview.
Riggs' road back to the UFC has been typically complicated. He was due to fight Set. 13 on a card in Brazil, stepping in for the injured Mike Rhodes against Paulo Thiago. But instead he found himself fighting for his life after his gun accidentally discharged in late July at his Arizona home.
"I'm a man that's handled guns my entire life and a brand new gun that should never malfunction malfunctioned," he explained.
A live round was stuck in the chamber. The safety was off but as he tried to dismantle the gun, the hammer dropped and Riggs was shot in the hand and thigh.
"I didn't think I was going to die, I knew I was going to die ... I accepted I was dead," he said.
Lying on the floor in a pool of blood, Riggs prepared for the worst.
"I said goodbye to my boy, who means everything to me. Who I'd die for at the drop of a hat. Saying goodbye to him was really really hard for me. Picturing my son having to grow up without a father, it changes you."
He called his wife, who summoned an ambulance. Because a gun was involved, police had to secure the area first. Riggs says it was 40 minutes before he made it to a medevac helicopter
Riggs was fortunate in the way the bullet struck his leg. "It was pinched in the right way that I didn't bleed out."
Doctors told him he would never fight again.
"I wouldn't accept it," said Riggs. "To think I went through all this for nothing, I finally got to where nobody thought I would be and this happens. I wouldn't accept it.
"My life has been horrible. I've had a horrible live and I've had a great life. But everything that I went through in my life I overcame and I've gotten through. So I just tried to put this toward that and push through and I did."
Today, Riggs says he's happy and in a "great place".
He used to fear thinking about losing. Now he understands anything can happen in mixed martial arts.
"Now I can go out and fight with a clear mind and know that whatever happens I'm OK with it. I just want to fight to the best of my ability. And I'm one of the best in the world so I think every time I fight it's going to turn out good."
The UFC lists Riggs' record at 40-14. Riggs himself says he has 65 wins and 14 losses, one of which came in a K-1 fight.
Riggs, who made his pro debut in 2001, acknowledges that in the past he had become jaded in the sport. Then he started training at the MMA Lab in Glendale, Ariz., determined to see how far he could go.
Riggs points to newly crowned welterweight champion (Ruthless) Robbie Lawler, another veteran who has made the most of his skills and reaped the rewards of hard work and dedication.
Riggs, whose nose is clear proof he doesn't work behind a desk, has been around so long that he has a tattoo that reads NHB, for no holds barred. It's a reminder of his early days fighting when there were few rules.
"Not many," Riggs said. "I couldn't bite a man's nipple off, that's about it."
With four years at the MMA Lab under his belt, Riggs says he trains smarter these days. "I haven't lost since."
Still, just making it to the Octagon again given his past is an accomplishment.
"I think the fact that I'm even fighting again and alive, the fact that I'm doing something that nobody thought I would ever do again is a huge win for me," Riggs said. "Beating Saunders is the icing on the cake."
Saunders (17-6-2) is 5-3 in the UFC, returning to the promotion in August to submit Chris Heatherly in the first round after a four-year absence. The six-foot-three Saunders is a graduate of Season 6 of "The Ultimate Fighter."
Former champion Junior Dos Santos, currently ranked second among heavyweight contenders, takes on No. 4 Stipe Miocic in the main event at US Airways Center. No. 14 lightweight Nate Diaz, Nick's younger brother, faces No. 3 Rafael Dos Anjos in the co-main event.
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