The parents of Washington State quarterback Tyler Hilinski say an autopsy performed after his January suicide showed evidence of chronic traumatic encephalopathy in his brain.

Speaking Tuesday to NBC’s “Today,” Mark and Kym Hilinski said the Mayo Clinic conducted the autopsy on Tyler, who died at 21 on Jan. 16 in Pullman, Washington. Police say Hilinski shot himself in the head with a rifle that belonged to a former teammate. The autopsy findings showed Stage 1 CTE.

“Did football kill Tyler? I don’t think so,” Kym Hilinski said in a Sports Illustrated documentary about Tyler’s life. “Did he get CTE from [playing] football? Probably. Was that the only thing that contributed to his death? I don’t know.”

Mark Hilinski told “Today” that the medical examiner determined Tyler “had the brain of a 65-year-old, which is really hard to take.” Tyler Hilinski’s parents said their son exhibited no obvious signs leading up to his suicide, and Tyler had never fired a gun until the day before his death. But they told Sports Illustrated that Tyler had become less responsive to calls and text messages late last season and after a family vacation to Mexico in January.

How can you knowingly play football when there’s so much evidence that taking concussions can destroy your brain? Not sure what the upside is anymore.