The NFL plans to contest the lawsuit filed against the league on behalf of Aaron Hernandez's daughter and stressed on Friday that any attempt to cast him as a victim is "misguided".
On Thursday, Boston University released the results of its post-mortem examination of his donated brain that found former New England Patriots tight end Hernandez had a severe case of CTE, the brain disease linked to concussions that can lead to violent behaviour and suicide.
Hernandez committed suicide in April while serving a life sentence for murder.
The lawsuit, filed by lawyer Jose Baez in US District Court, claims the NFL and the Patriots failed to protect players' safety. The league, though, says the lawsuit is flawed.
In a media briefing, NFL spokesman Joe Lockhart said: "We are reviewing the lawsuit. On first blush, we believe it contains significant legal issues.
"His personal story is complex, it doesn't lend itself to simple answers. He was convicted of a homicide and his well-documented behavioural issues began long before he played in the National Football League.
"The real victims are the friends and family of those he killed, along with his young daughter."