Brain researchers have once again found the signs of a degenerative brain disease in the brain of a former NHL player. But this time they found it in someone who wasn't a brawler: former Buffalo Sabre Rick Martin.

Martin died of a heart attack in March at the age of 59. His family donated his brain to the so-called "brain bank" at Boston University, the Center for the Study of Traumatic Encephalopathy.

Researchers announced Wednesday that they had found distinct signs of the brain disease CTE, or Chronic Traumatic Encephalopathy, in Martin's brain. The disease is thought be caused by repeated brain injuries and can bring on behaviour changes, memory problems, and dementia.

He is now the third former NHL player to have been shown to be suffering from CTE. But what makes Martin's case unique is that he is the first hockey player found with the disease who did not play an "enforcer" role, regularly participating in on-ice fights.

The Boston researchers said Martin's case was considered Stage 2 on its four-stage scale. That stage made it unlikely the disease has begun to significantly affect his memory, thinking skills or behavior.

Martin did not regularly fight during games, but he did have at least one severe concussion. That was more than 30 years ago, in 1977, when his head hit the ice while not wearing a helmet. The hit caused Martin to immediately begin to convulse.

Martin began wearing a helmet after that accident and wore it until he retired.

After that hit, he went on to play two more NHL seasons with the Buffalo Sabres -- where he was part of the legendary "French Connection" line with Gilbert Perreault and Rene Robert – and later, with the Los Angeles Kings.

Records show he was involved in only 14 fights in 14 seasons in junior hockey and the NHL. He was never diagnosed with any other concussions, nor did he suffer any other brain trauma outside hockey.

Chris Nowinski, a founder of the Sports Legacy Institute at Boston U, says the findings about Martin are significant.

"Rick Martin's case shows us that even hockey players who don't engage in fighting are at risk for CTE, likely because of the repetitive brain trauma players receive throughout their career," Nowinski said Wednesday in a statement.

Further details of Martin's brain tissue analysis will be released in a medical journal. But the Center for the Study of Traumatic Encephalopathy said his family wanted these initial findings to be made public "to raise awareness of the dangers of brain trauma in sports and encourage greater efforts to make sports safer for the brain."

The Boston team has studied the brains of over 70 former athletes; more than 50 have shown signs of CTE. They include 14 of 15 former NFL players. It's also been found in professional wrestlers, boxers, and the brains of former NHL tough guys Bob Probert and Reggie Fleming.

It's even been found in young college and high school football players.

Dr. Robert Cantu, a CSTE co-director, says it's interesting that Martin's CTE had advanced to only stage 2 by the time of his death at 59.

"By that age, most cases in our brain bank have advanced to stage 3 or 4," he noted in a statement.

He said there appear to be a number of variables that affect one's risk of CTE, including one's lifetime exposure to brain trauma, genetics, and other factors.

Robert Stern, another CSTE co-director, says researchers are now trying to better understand those risk factors.

"We believe that repetitive brain trauma is a necessary factor for developing the disease, but not a sufficient factor. We now must learn why some people get the disease and others don't and why CTE progresses more quickly and severely in some individuals than in others," he said.

CTE can only be diagnosed after death. More than 500 current athletes have committed to donate their brain to the BU CSTE after death, including over a dozen former hockey players.

There are 96 brain specimens in the program's brain bank at present. The brain of the enforcer Derek Boogaard, who died last May at 28 of an overdose of painkillers and alcohol, is currently being studied.