A top NFL safety official said Tuesday that "football has never been safer" and that the league respects the decision of a 24-year-old linebacker to retire because he is worried about long-term brain injury.
"We are seeing a growing culture of safety," Jeff Miller, the NFL's senior vice president of health and safety policy, said in a statement. "Everyone involved in the game knows that there is more work to do and player safety will continue to be our top priority."
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"By any measure, football has never been safer and we continue to make progress with rule changes, safer tackling techniques at all levels of football, and better equipment, protocols and medical care for players," he said.
Chris Borland, who played a promising rookie season last year for the San Francisco 49ers, told ESPN on Monday that he is walking away because he doesn't think football is "worth the risk." Miller, the league official, said that "playing any sport is a personal decision."
The long-term health damage caused by player concussions is one of several crises confronting Commissioner Roger Goodell. He trumpeted improved safety figures at his season-ending press conference before the Super Bowl. The league says concussions were down 25 percent last year.
This article originally appeared on NBCNews.com.