A post-mortem analysis of Jovan Belcher’s brain revealed a key signature of chronic traumatic encephalopathy, concluding that the 25-year-old former University of Maine football player was likely suffering from the degenerative neurological condition.

The news is a potentially game-changing development at the intersection of two of the NFL’s biggest threats — head injuries and domestic violence.

Belcher starred at Maine through the 2008 season and was a starting linebacker for the Chiefs who shot and killed his girlfriend, Kasandra Perkins, then himself on Dec. 1, 2012. CTE is a degenerative brain disease found to cause dementia, aggression, confusion and depression among people who’ve suffered repeated head trauma, including football players.

The analysis was performed in New York at the request of lawyers representing the interests of Zoey Belcher, the 2-year-old daughter of Jovan Belcher and Perkins. The results can be used in ongoing litigation, both against the Chiefs and NFL. The Chiefs declined comment. The NFL did not immediately respond.

CTE has been found to cause erratic and sometimes tragic behavior by some NFL players, notably Hall of Fame linebacker Junior Seau, who killed himself last year. The disease, only recently diagnosable before death, has often been found in former and longtime football players.

Matt King, Belcher’s former teammate at Maine, said he was not surprised to hear of the CTE findings.

“If you were to take a survey of football players, I guarantee you that 80 or 90 percent of them would have some kind of brain trauma,” he said. “I’m not saying it’s what’s to blame for what happened with Jovan’s situation. It just adds to the fact that maybe we should do something to prevent this.”

King, who now serves as Maine’s head strength and conditioning coach, is trying to do just that. He is working on a master’s degree in exercise science and kinesiology, with an emphasis on concussion prevention.

King was a mentor to Belcher with the Black Bears. He was a standout linebacker and defensive end from 2002-06; the latter two seasons were Belcher’s first in Orono.

“I have fond memories of him when he was younger. I passed my number (9) down to him when I left. I looked at him as a little brother,” King said. “He always had a smile on his face and he was willing to help out any teammate in need. Those are the memories I have of him.”

The two last spoke shortly before the 2012 football season, just after the birth of Belcher’s daughter.

“He was just mentioning that it’s an everyday battle to keep your job in the NFL. People don’t understand the pressure that the guys are under, especially if you have family, you have mouths to feed,” King said. “He talked about how, as a small-school guy, they’re always looking at you as you could be the first guy out the door. They look at you as a fringe player.

“I feel for his child because that child has no parents right now. That’s the worst part of the whole situation. I wish I had spoken to him so I could see what frame of mind he was in. Because the Jovan I remember at Maine wasn’t the guy I saw portrayed in the media.”

Belcher is among the younger known cases of CTE. He played four seasons in the NFL, all with the Chiefs, and did not have a documented history of concussions. But friends have said Belcher had multiple concussions, and after the murder-suicide, stories emerged that he had become unpredictable and irritable. Belcher’s lawyers have consulted with a psychologist who is willing to state Belcher’s behavior is consistent with CTE.

Former professional wrestler Chris Benoit was found to have CTE after killing his wife and son before killing himself in 2007. But murder or other violence against others has not typically been associated with CTE.

Bennet Omalu, who is credited with discovering CTE, and Julian Bailes, founder of the Brain Injury Research Institute, each said that Belcher’s brain could provide important scientific findings.

Belcher’s daughter and mother would be eligible for up to $4 million under the proposed concussion settlement between the NFL and former players if it can be shown that Belcher had CTE. Lawyers representing Belcher’s daughter have also filed a wrongful-death suit against the Chiefs, and would have to convince a jury that CTE was more likely than not to have caused or been a contributing cause to Belcher killing Perkins and then himself.

Last year, at the request of Belcher’s family, his body was exhumed at North Babylon Cemetery in his hometown of Bay Shore, New York. It was believed to be the first exhumation of a former NFL player, and done with the hopes of finding answers or at least clues about why Belcher shot Perkins nine times at the home they shared in Kansas City before driving to the Chiefs’ practice facility and shooting himself in the head, leaving Zoey, then 3 months old, orphaned.

The specimen was obviously damaged, but preserved enough for examination. Piotr Kozlowski, dean of research and professor of pathology at Touro College of Osteopathic Medicine in New York City, signed the report that concludes: “The microscopic findings of neurofibrillary tangles in young person are fully consistent with the pathological presentation of Chronic Traumatic Encephalopathy (CTE) as it is reported in the available medical literature.”

Belcher’s murder-suicide is the worst possible example of domestic violence, and these findings come as the NFL is under attack for its handling of domestic violence.

Ray Rice was initially suspended for two games, then suspended indefinitely for punching his then-fiancee unconscious at a New Jersey casino in February. San Francisco defensive lineman Ray McDonald continues to play after an alleged assault of his fiancee, and Panthers defensive lineman Greg Hardy continues to play while appealing a domestic violence conviction.

Staff Writer Mark Emmert contributed to this story.