Former New York Giants safety Tyler Sash, who died in September at age 27 from an accidental overdose of pain medication, had a high level of CTE.
The New York Times reported Tuesday the findings from researchers at Boston University after Sash's family donated his brain to be studied for chronic traumatic encephalopathy.
The Times reported that "representatives from Boston University and the Concussion Legacy Foundation notified the Sash family that CTE had been diagnosed in Tyler's brain and that the disease, which can only be confirmed only posthumously, had advanced to a stage rarely seen in someone his age."
The CTE scale rates severity from 0 to 4 and Sash had progressed to Stage 2, according to the Times report, and that is about the same stage Junior Seau was at when he committed suicide at age 43.
Sash played only two years in the NFL, with 23 regular-season appearances and four in the postseason. He appeared in 37 games at the University of Iowa.
Months after the Giants' Super Bowl victory, Sash was suspended for four games in 2012 for violating the NFL's performance-enhancing substances policy by testing positive for Adderall.
According to the Times, Sash dealt with "confusion, memory loss and minor fits of temper" that affected his ability to find meaningful employment after he was released by the Giants in 2013. The Giants reached an injury settlement with Sash after he suffered a concussion in the preseason finale against the New England Patriots.
According to his brother, Sash suffered at least two concussions in high school, one in college and two in the NFL.
Sash's mother told the Times that the finding of a high level of CTE helps explain her son's behavior.
"Now it makes sense," Barnetta Sash told the Times. "The part of the brain that controls impulses, decision-making and reasoning was damaged badly."