Chris Borland's choice to walk away from the royalties of the NFL and abandon a very promising career made national headlines, and the reason behind it is still a major topic in sports today.
Is the risk of head trauma worth the money, fame and overall lifestyle that comes with being an NFL star?
Borland didn't think so.
"I couldn't really justify playing for money," Borland told PBS in a Frontline special. "And I think what I wanted to achieve put me at too great of a risk, so I just decided on another profession.
"[Being drafted] was a dream come true, I remember my brothers jumping up and hugging me. It's surreal to see your name across the ticker, the analyst start to talk about you, and then you're playing in the NFL."
But shortly after being drafted by the 49ers 77th overall in the 2014 NFL Draft, Borland began researching the game.
"It's tough," the Ohio native said. "You understand on a certain level what you're doing, but you don't know the science behind it."
To get a better understanding, Borland called the leading brain scientist at Boston University, Robert Stern.
Stern quantified the physicality of the game to Borland: "Each time [a collision] happens, it's around 20G or more. That's the equivalent of driving a car 35 miles per hour into a brick wall...1,000 to 1,500 times per year."
After speaking with the neuropsychologist, Borland filed for retirement that very day.
"The idea that just the basis of the game, repetitive hits bring on a cascade of issues later in life, that changes the game for me," the former 49ers linebacker said.
Borland also responded to an interview of commissioner Roger Goodell with Charlie Rose, where Goodell said the NFL has never been more exciting and competitive, and has never been safer.
"It's dishonest, and I don't think it's responsible to say that the game is safer. I think that's just not true. The players themselves on the field, they know—they'd scoff at that. That's not accurate.
Borland, in conclusion, reacted to the fact that the 49ers asked him to return most of his $617,436 signing bonus.
"I didn't play for money, I didn't leave for money. I'd happily pay the pre-tax value and get on with my life.
"Last year the NFL commissioned actuaries to estimate how many NFL veterans would have brain damage, and the number they came up with was 3 out of 10. So if I turn on a game and a third of the guys will have brain damage in life, I can't really support that. And I don't really watch football anymore, if it's on, I may peak at it, but..."
Borland played one year in the NFL, starting eight of 14 games played. The Wisconsin product finished with 107 total tackles, one sack, five pass deflections and two interceptions.