Roger Goodell has put a heavy emphasis on player safety during his time as NFL commissioner and according to people close to Goodell, the reason is he fears a player will die on the field if changes are not made.

In a profile written by Don Van Natta Jr. for ESPN the Magazine, friends say Goodell has told them privately that he believes a player could die on the field if the current culture doesn't change. An unnamed member of the Hall of Fame who speaks with Goodell regularly said it's one of the commissioner's greatest fears.

"He's terrified of it," the player said, according to ESPN. "It wouldn't just be a tragedy. It would be awfully bad for business."

According to Van Natta's profile, Goodell often references President Theodore Roosevelt, who pushed for reforms to college football in the early 1900s after several college football players died from skull fractures. Those innovations helped propel football into the next era, something Goodell is trying to emulate.

While his goal may be to protect players and prevent the second on-field death in NFL history, Goodell's practices haven't been widely accepted by the players. In a recent USA Today poll of 300 active players, 61 percent said they disapprove of the job Goodell is doing. Players have voiced their criticisms publicly, including Atlanta wide receiver Roddy White, who said Goodell's term as commissioner has been "like a dictatorship."

"Whatever he says, that's the end of it," White said, according to ESPN.

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