Former running back Rob Lytle, the Broncos' second-round 1977 draft choice who played seven seasons for the team before injuries forced his retirement, died of a massive heart attack at age 56 in 2010.
His son, Kelly, has written a book, "To Dad, From Kelly" about their relationship. He noted this week that the family's donation of his father's brain and spinal column to the Boston-based Sports Legacy Institute came early in the study of chronic traumatic encephalopathy (CTE). Doctors told the family four years ago that Rob had "moderate to severe" CTE.
"Knowing that, a lot of the struggles he had later in his life started to make a lot more sense," Kelly Lytle said.