Chronic traumatic encephalopathy, the type of brain damage plaguing the NFL and turning the lives of former players to hell, has always been confirmed after a player's death.
But one study published this week says researchers were able to diagnose CTE in a former player while they were still living – and it's a former Minnesota Viking whose slide into dementia before death was well-chronicled.
Fred McNeill played linebacker for Minnesota over the course of 12 seasons. He was a first-round pick out of UCLA, and appeared in two Super Bowls with the Vikes.
He died in November of 2015, at the age of 63, after a long battle with ALS.
On Thursday, it was revealed that a former player had been tentatively diagnosed with CTE via an experimental brain scan in 2012, CNN reports. An autopsy after his death confirmed that diagnosis.
It's the first time CTE is confirmed to have been diagnosed in a living person.
And while he's not named in the report, that person, according to CNN, is McNeill.
They were able to tell because the 2012 scan showed spots on McNeill's brain that appeared damaged, USA Today explains. The autopsy found the protein associated with CTE in those exact same spots of the brain.
“There’s more to understanding, but this is a nice demonstration of the correlation of a living scan and an autopsy of the brain," Julian Bailes, co-director of NorthShore University Health System, told USA Today Sports.
The final years of McNeill's life were difficult.
A CNN story shortly after his death was titled "The tragedy of Fred McNeill." It describes McNeill – who became a lawyer after his football career – slowly losing his memory, getting headaches and uncharacteristically losing his temper.
If doctors are able to identify CTE in living players, that could be a huge step for the NFL, SB Nation says.
Those with early markers could be told they can't play, which might lessen CTE's effect later in their lives. It could also lead to better treatment.
GQ wrote a devastating account well before McNeill died, stories of repeated conversations, failed neurological tests, and the decline of a once brilliant man.
"She had no idea, back then, that he was sick. She had no idea he was losing his mind. Something neurological, the doctors are now saying, some kind of sludge blocking pathways in his brain. Would it have made a difference if she knew? Of course it would have. But you can't think like that. And you can't give a s--t about people whispering behind your back."