San Francisco 49ers Rookie Chris Borland Retires After Researching Concussions San Francisco 49ers star rookie Chris Borland is ending his promising football career due to concussion safety concerns, ESPN reports. The announcement comes at a time when the National Football League has been heavily criticized over its policies when it comes to repetitive head trauma leading to brain damage. Borland is the third player in his twenties to retire in the past week. In an interview with Outside the Lines on Monday, the 24-year-old linebacker said his own research on concussions and discussions with friends, family and teammates led to his decision to retire early. "I just honestly want to do what's best for my health," Borland said. "From what I've researched and what I've experienced, I don't think it's worth the risk." Borland told Outside the Lines that ultimately, his health comes first: "I feel largely the same, as sharp as I've ever been, for me it's wanting to be proactive. I'm concerned that if you wait till you have symptoms, it's too late. ... There are a lot of unknowns. I can't claim that X will happen. I just want to live a long healthy life, and I don't want to have any neurological diseases or die younger than I would otherwise." According to ESPN, "more than 70 former NFL players have been diagnosed with progressive neurological diseases following their deaths." The associated consequences of traumatic brain injuries can include memory loss, depression and brain damage. In September 2014, the NFL finally disclosed that "nearly three in 10 former players will develop debilitating brain conditions," about twice the rate of the general population. The revelation was part of a larger lawsuit filed by players against the league. Borland, who came to the league from the University of Wisconsin, said having two diagnosed concussions during his youth from soccer and football was enough to make him worried about his own future health. Ultimately, he decided, it was not worth the risk to end up like Mike Webster and Dave Deurson, NFL icons and athletes he admired who were diagnosed with chronic traumatic encephalopathy after their deaths. Trent Baalke, the general manager of the 49ers, said in a statement that Borland's decision was "unexpected," but "respected." “While unexpected, we certainly respect Chris’ decision... From speaking with Chris, it was evident that he had put a great deal of thought into this decision. He was a consummate professional from day one and a very well respected member of our team and community. Chris is a determined young man that overcame long odds in his journey to the NFL and we are confident he will use the same approach to become very successful in his future endeavors. We will always consider him a 49er and wish him all the best.” This has been updated to include comments from the 49ers.