For years, the NFL has denied that it was aware of a link between playing football and players suffering brain injuries. Now, evidence has been uncovered that calls that claim into question.

The league’s retirement board awarded disability payments to at least three former players after determining that the sport caused their brain injuries, according to a joint report by FRONTLINE and ESPN’s Outside the Lines.

An investigation led by Mark Fainaru-Wada and Steve Fainaru has discovered documents showing the league paid out at least $2 million in disability benefits to players in the 1990s and 2000s after determining that the NFL was responsible for their debilitating mental injuries.

That action, which resulted in payments to Hall of Fame center Mike Webster and others, could prove that the league was indeed aware of the dangers the sport posed, and therefore it can be held liable for damages in court. However, in the face of ongoing lawsuits by former players, league spokesman Greg Aiello clarified that the retirement board is independent from the NFL and its players’ association.

Documents found show that the league’s board decided that “repeated blows to the head had left Webster … ‘totally and permanently’ disabled” from his years playing in the NFL.

Webster, who died in 2000 at age 50, was the first player diagnosed with Chronic Traumatic Encephalopathy (CTE), a disease that mimics ALS and one that sports fans have become all too familiar with in recent times.

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