He was only 25, but Jordan Parsons was a cage fighter, a professional mixed martial artist who on his best nights beat his opponents into submission. On his worst nights, Parsons was sent spiraling to the canvas by devastating blows to his head.
Now, six months after he was struck and killed as a pedestrian by an alleged drunken driver, Parsons is the first fighter in the multibillion-dollar MMA industry to be publicly identified as having been diagnosed with the degenerative brain disease known as chronic traumatic encephalopathy (CTE).
The diagnosis was disclosed to the Globe by Dr. Bennet Omalu, a forensic pathologist who first discovered CTE in a professional football player (in 2003) and a professional wrestler (2007).
Omalu also announced the discovery of CTE in professional wrestler Jon Rechner, whose ring name was Balls Mahoney, as well as signs of early stages of the disease in Rechner’s tag team partner, Brian Knighton, who went by Axl Rotten. Both died this year at age 44.
Rechner and Knighton were known on the professional wrestling circuit as “The Hardcore Chair Swingin’ Freaks,” and Rechner is the third professional wrestler who has been publicly identified as having been diagnosed with CTE — and the first since 2009.
Their diagnoses come as World Wrestling Entertainment, the industry’s largest promoter, defends itself against lawsuits alleging the company placed its business interests above the health and safety of its performers.
WWE spokesman Brian Flinn said by e-mail that the company would decline to comment until it has reviewed the research on the diagnoses. He suggested that Konstantine Kyros, a Hingham lawyer who represents more than 60 professional wrestlers, was “pushing’’ the CTE story to counter negative publicity about the WWE’s court motions to sanction him for improper conduct — an allegation Kyros denied.
The WWE lawsuits are similar to complaints brought by former players against the National Football League after Omalu’s landmark diagnosis in 2003 of CTE in the late Pittsburgh Steeler Mike Webster’s brain. The football cases led the NFL to reach a $1 billion settlement with the players.
The National Hockey League faces a similar legal challenge, and the Parsons case signals the possibility of court action against the MMA industry by participants of the combat sport. The industry’s leader, the Ultimate Fighting Championship, was sold to a Hollywood conglomerate in July for $4 billion.
“These findings confirm that the danger of exposure to CTE is not limited to just football, hockey, and wrestling,’’ Omalu said in an interview. “Mixed martial arts is also a dangerous sport, and it’s time for everyone to embrace the truth.’’
Parsons, whose nickname was “Pretty Boy,’’ was a contract fighter for Bellator MMA, which is owned by Viacom. The media giant bought a controlling stake in Bellator in 2011 for a reported $50 million and airs its fights on the Spike television network.
Bellator president Scott Coker issued a statement saying, “Jordan was a shining star in this sport and a beloved member of the Bellator family who we miss very much and we continue to honor through the ‘Jordan Parsons Memorial Scholarship Fund.’
“Bellator MMA is committed to the safety of our fighters and has been a strong supporter of the Cleveland Clinic [Professional Fighters Brain Health Study] for the last few years.’’
CTE can only be diagnosed through postmortem brain autopsies. The autopsies on Parsons, Rechner, and Knighton were conducted by Dr. Julia K. Kofler, a neuropathologist at the University of Pittsburgh Medical Center Presbyterian. The university is affiliated with Omalu’s charitable foundation, which he created in 2015 before the release of the movie “Concussion,’’ a dramatization of the NFL’s resistance to his CTE research.
Omalu said he reviewed Kofler’s studies and endorsed her findings.
“As a scientist, a physician, and a person of faith, I beg everybody involved with these sports to come together and identify the problems and find solutions,’’ Omalu said.
Parsons, a former high school wrestler in Michigan, began competing in MMA events at age 17. He turned pro at 20 and soon captured the Championship Fighting Alliance’s featherweight title.
Then came medical trouble. After rolling undefeated through his first seven professional bouts, he lasted only 71 seconds in his eighth match, in 2012, before he was sent reeling to the mat by a knockout punch. A full year passed before Parsons fought again.
His mother, Anna Morsaw, sent a video of the knockout to Kyros, who procured Parsons’s brain for the autopsy. She also sent a video of Parsons’s final match, in 2015, in which he went wobbling to the canvas after a thunderous kick to his head.
Still, Parsons was a rising star, and he was training with an elite professional team, the Blackzilians, in Boca Raton, Fla., before his death. On May 1 in nearby Delray Beach, he was struck in a crosswalk by a Range Rover that seconds earlier had allegedly been traveling more than 100 miles per hour in a 45-mile-per-hour zone. He died three days later.
Omalu said it was “impossible’’ for Parsons’s CTE to be caused by the accident “because it is a chronic disease that develops over time.’’
Kyros, who helped represent hundreds of players covered by the NFL settlement, said he has no plans to sue Bellator in the Parsons case. He said he procured Parsons’s brain in part to explore whether athletes in sports other than football, hockey, and boxing were at risk of CTE.
“Out of the tragedy of Mr. Parsons’s death, I hope the results serve to both warn and educate other athletes and their doctors about the hidden risks involved,’’ Kyros said.
Parsons’s mother declined to comment publicly on the diagnosis, indicating she was too distraught about his death and the pending criminal prosecution of the driver who allegedly killed him.
As for Rechner and Knighton, they also started wrestling as teenagers. By their 20s, they were performing in a wild frontier of professional wrestling in which their theatrics were fraught with violence. They wielded metal chairs and barbed-wire-covered bats, among other objects.
The professional wrestling industry, which is classified as entertainment rather than sports because the outcomes of matches are predetermined, has since banned the dangerous tactics that were prevalent when Rechner and Knighton performed on the Extreme Championship Wrestling (ECW) circuit in the 1990s and early 2000s.
But many wrestlers have said they experienced repeated head blows while training and performing for the ECW and WWE. Rechner and Knighton performed briefly for the WWE after it bought ECW in 2003.
Rechner was said to have experienced memory problems, a symptom of CTE, before he died of a heart attack at his New Jersey home in April. His mother, Suzanne Rechner, said his diagnosis should serve as a warning.
“I hope these results help other wrestlers learn about the health problems they are going to have in the future,’’ she said. “WWE, just like the NFL, should take care of their people.”
The WWE has cited positive results in a concussion management program it established in 2008 to complement its talent wellness protocols and better protect its performers.
Two months after Rechner’s death, Knighton was found dead of an accidental heroin overdose in suburban Baltimore.
His family said he was plagued by debilitating physical and mental health problems stemming from his years as a professional wrestler. They said he was unable to conquer his opioid addiction despite a WWE-funded rehab stint.
His father, Sonny Knighton, described him as a victim of his chosen career.
“My message to anyone who is interested in going into professional wrestling is to stay away from it,’’ Sonny Knighton said. “Unless you’re one of the top performers, no good comes of it.’’