The decision was about coming to terms with the totality of my concussion history. I gave everything I had, and when I couldn’t do that anymore, I retired out of respect for the sport—and my health

I made my decision to retire when I entered the locker room for what would be the last time. I was not going to keep playing football unless I could block out everything. If I could push all the information about head trauma and my realized risk so far to the back of my mind that it wouldn’t affect my play and put me at further risk, then I would push on in pursuit of just a few more moments of elation.

I started playing this game in third grade, a year earlier than my school district in Plymouth, Minn., allowed. My father coached my older brother’s team, and he let me practice with the boys who were a year older. From then on I did anything to be on the field. As a seventh-grader I starved myself for days to make weight limits. In high school and at Stanford, I played through fractured bones, sprained ligaments, muscle strains, bone spurs and shoulder dislocations. For 15 years I never missed a practice or a game.

I tried to model myself after London Fletcher, a football marvel who went undrafted (as I did) and played in 256 consecutive games—with 215 consecutive starts—over 16 NFL seasons. There’s a certain amount of luck involved in a streak like that (and to a lesser degree, a streak like mine), but I believe the driving force is a certain mentality. It’s denying yourself any sense of entitlement about having earned a day off. It’s about believing that as long as your teammates are giving their blood, sweat and tears for a common cause, then I must be right next to them, sharing the experience.

That’s why it’s so difficult for me to admit, at 23 years old, that my time in the NFL is over.

* * *

During a padded practice in training camp last summer, I suffered my third concussion since high school. I met a fullback in a gap and his facemask caught the left side of my helmet. I went through the rest of practice with a headache and tunnel vision, and then went to the trainers after practice and asked them to check me out. I passed balance, vision and memory tests, and once I realized my memory was fine, I didn’t press the issue.

For the next few days I had a raging headache. I drank several liters of Pedialyte and gallons of water trying to convince myself that dehydration was the cause. I knew that if I told the trainers about my headache persisting then I would have to be reevaluated and risk missing practice or even game time.

I think it’s easy to look at me and say he must not love it, want it or need it. And that couldn’t be further from the truth. The hardest thing I’ve ever done was going up to Rex Ryan’s office and telling the man who gave me a chance that I was done playing.

Just a few months earlier, the Bills had signed me to a three-year contract, but there were few guarantees. Being an undrafted rookie free agent means your chances of making the 53-man roster are slim—even if you’re fully healthy. Other undrafted players were missing snaps from soft tissue injuries and I saw the repercussions. If you can’t take the snaps to learn and practice a technique or play, then you’ll miss the next step. The effect snowballs.

Do guys get second chances? Do players miss snaps and still make the team? Yes. But it’s not the sort of thing you leave to chance. If coaches can’t see you practice, they can’t rely on you when it counts. When their jobs are on the line, the priority is playing guys whom they trust to perform. I knew I couldn’t sit out. I couldn’t risk coming this far toward my ultimate childhood dream only to let this stop me short. So I did everything I could to hide it, and I didn’t tell a soul.

* * *

Having suffered four concussions since high school, Tarpley didn’t believe he could keep subjecting his head to the kind of hits that come with playing linebacker in the NFL. AP :: Michael Leff/Getty Images

Although there is still much to be learned about concussions and traumatic brain injuries, one conclusion drawn from recent research stood out as I contemplated my options this offseason: Studies show that with each concussion, the risk of another becomes more likely.

I suffered my first concussion in high school, and my second at Stanford, during the PAC 12 championship game in 2014. I decided to hide my third concussion, during training camp last summer, in the hopes that it would be my last, but I wasn’t so lucky. My fourth and hopefully final concussion came against the Jaguars on Oct. 25 in London. On my first defensive play, I hit the oncoming offensive tackle, shed the block, and just as I was lowering myself to tackle the running back, he was hit from behind by one of our defensive linemen and the crown of his helmet connected with my temple

My vision started to close in on me and I blew a coverage assignment on the next play. I got pulled off the field, and I tried to buy myself some time. When asked about the blown coverage, I told a coach that I made a mistake and it wouldn’t happen again. At that point the Jaguars had a first-and-goal and brought out their big personnel, which we matched. “GOAL LINE X! GOAL LINE X!” I cherished these moments. My coaches had trusted me to be the X on goal line, a position typically reserved for a team’s best corner or a defensive back that can also play in the box and make tackles. I refused to let them down, so I buckled my chinstrap and went to work.

I have always had aspirations to succeed and contribute to society beyond football. For better or worse, concussions have ushered in this new chapter of my life sooner than I anticipated.

The next four plays are still a blur. I managed to find my correct alignment through the horse blinders, and I just played on instinct. I told myself to hit whatever comes my way and don’t stop moving my feet. We stopped them on all four downs. But I knew something was wrong with my head, and pulled myself out of the game after that series.

The trainers diagnosed me with a concussion and took me to the locker room, where I watched the rest of the game on TV. The vision problems continued and were compounded by a migraine headache. Then I lost feeling in my fingers, arm and shoulder on the right side of my body (the hit had also injured nerves and muscles in my neck and shoulder). During a nauseating eight-hour flight home, I thought back to the concussion in August. It was caused by a hit to the same side of my head and led to the same vision problems. It was too real to ignore. I brought this to the attention of team doctors and an independent doctor, whom I was mandated to see by league rules.

Every medical professional I talked to during those weeks after the London game told me that I wouldn’t step on the field until I was fully recovered, no matter the timeframe. At least one doctor advised me to think about my concussion history and make an educated decision about my future in this profession. I was also told I would be out for at least the year or longer if I suffered another concussion. They knew about my concussion in college, but I withheld information about the one in high school, and I clung to the fact that I’d never been knocked unconscious.

I thought about how many others had retired after multiple college concussions without ever getting to the NFL, and how I had no idea how many concussions I’d truly suffered because I was rarely honest about my symptoms. Still, my main goal at the time was to remain on the field. Players get cut every week in the NFL, and being an undrafted free agent who missed time in his first season didn’t sound like a comfortable position to be in. Luckily, our bye week followed the overseas game; I had two weeks from the concussion before we would play again and I decided that would be enough. The trainers and doctors I interacted with were always inquisitive and had my health in mind. I spent those next two weeks never feeling “normal” but always saying I was feeling better, even if that meant bending the truth.

After playing in the next game, I postponed thinking about the future until the season was over. Three weeks later I got cut, missed one game while on the practice squad, and then re-signed the very next Monday. I finished the last four games with four tackles on special teams, two successful starts on defense and memories that I will cherish forever. I believe you won’t find more selfless people at the literal peak of their profession than in NFL locker rooms. My time was brief, but my Bills teammates were special.

For the first three months of the offseason, I spent the majority of my time in California, working out at Stanford while doing research about my health and my options. I shared my thoughts with a few former teammates, mostly because I wanted to center my choice on my personal goals. No matter what I ended up doing, the last thing I wanted was for my choice to be considered part of a political agenda or an indictment on the game that has provided me so much joy and so many opportunities. Though my parents have all my trust, and though I value the opinions of my closest friends and mentors, I refused to let them in on my deliberations. If I did continue playing, I did not want them to have to live with the knowledge that if something happened to me, they could have prevented it.

No educated person seems to be denying the relationship between brain injuries and football, yet there are no definitive measures. We still can’t answer the question of how much is too much. I was on the fence. I had to decide if I wanted to keep walking that line made thinner and thinner by my concussions.

I made the drive from my parents’ house in Indianapolis to Buffalo a few weeks before offseason workouts began, hunting for that gut-feeling to guide me. Ultimately, even those steps back into the locker room couldn’t suppress what my perceived danger had become. Not wanting my childhood dream to end, I slept on it for days. I had to be sure. The hardest thing I’ve ever done was going up to Rex Ryan’s office and telling the man who gave me a chance that I was done playing.

This was not about me thinking I couldn’t physically play more football without suffering crippling brain damage. I have no current residual effects that I am aware of, cognitively or physically. The decision I made to retire from football is about coming to terms with the totality of my concussion history and what is asked of me as a linebacker. My position put me at an elevated risk for further injury with the likelihood that I would be exposed to hundreds or even thousands of similar situations. I understand that in order to continue playing at the level expected of me, I would have had to put myself in those exact scenarios.

I will never know if I would have received life-impairing damage to my brain somewhere down the line. There is a chance I could have played five more years in the NFL and lived a long, happy and healthy life. The elusive second contract that every NFL player aspires to was a big consideration of mine.

I think it’s easy to look at me and say it’s no wonder a middle-class kid with a Stanford degree is walking away from football; he must not love it, want it or need it. And that couldn’t be further from the truth.

Make no mistake, the elusive second contract that every NFL player aspires to was a big consideration of mine. Neither of my parents have college degrees. They have dealt with more than their fair share of rough patches, hardships and everything else life throws at you, yet they gave their two sons the opportunity and the inspiration to pursue excellence, no matter the field.

They taught me that money, status, and trivial things are not what matter in life, and that if you work hard enough you will overcome. We learned to outwork everyone, have no regrets, and to be the best at whatever you choose. That’s what drove me during the recruiting process in high school, when I was viewed as undersized and not athletic enough. I heard more of the same before the draft, when I was described as “instinctual” and “smart” but too slow to become a playmaker and a long shot to make a team. I had 54 college games with at least one tackle, 50 starts, second-team All-PAC-12 honors, yet none of it mattered to the pundits. More doubters, more fuel to the fire.

I dedicated a huge part of my life to making plays in the NFL, and for a short time, I did. I played in 15 games as a rookie, started two, forced one fumble and picked off two passes in my final two games. I owe a great deal to the sport that provided life lessons that I imagine are extremely difficult to replicate. That said, I have always had aspirations to succeed and contribute to society beyond football. For better or worse, concussions have ushered in this new chapter of my life sooner than I anticipated.

* * *

There’s an old myth about the Spanish conquistador Hernán Cortés that seems to apply to the NFL. As the story goes, Cortes and a small army landed at Veracruz in modern-day Mexico in 1519, driven by “Glory, God and Gospel.” So as to leave themselves no other option but victory over the inhabiting Aztecs, Cortés instructed his soldiers to “burn the ships.”

From my experience, a lot of guys in this league similarly operate without a Plan B. For many, there is no better motivation to succeed at football than a lack of options.

I created a Plan B for myself, through education, but I never approached my career with an out in mind. I treated every day as though the ships were burned. That mindset is what I would consider the biggest driving force behind why anyone ever makes it to the pinnacle of his or her respective career. It’s why I got as far as I did. I was going to do whatever it took to make it.

As a four-year starter and a team captain who played in three BCS bowls and won two PAC 12 championships at Stanford, I never cared about individual successes. What I wanted to do was put my head down, shut my mouth, and get to work. This was always my motto, even in the NFL. In my opinion, the greatest achievement in any walk of life is consistency. The greatest compliment is a coach, boss, or peer having unwavering confidence in you no matter the circumstance. If all I ever did was make an impact on my teammates, coaches and anyone else that I interacted with in the world of football, then my career was a success. I want to thank all of them for everything they drove me to be, and I want them to know that I gave the game everything I had. When I decided I couldn’t do that anymore, I walked away from football out of respect for the sport.

I will never know if I would have received life-impairing damage to my brain somewhere down the line. There is a chance I could have played five more years in the NFL and lived a long, happy and healthy life. But going forward my life will be entirely what I make of it. My happiness is in my hands.

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