From 2006-18, fans eagerly anticipated Brandon Marshall’s next move. The wide receiver leaped from team to team like a journeyman. Unlike most constantly moving pieces, however, he brought top-flight talent to the position in the process. Marshall joining an NFL team was a gift.

Which raises the question: Why did Marshall keep getting shipped around? Why wasn’t such an obviously talented player a ripe NFL trade target? Marshall himself ended up being the best source for the answer.

Breaking records and laws: Brandon Marshall’s NFL career

On December 13, 2009, Marshall set an NFL record for receptions in a single game. His 21 receptions, according to ESPN, passed up Terrell Owens’ 20 from back in 2000. Pro Football Reference notes another historic feat of Marshall’s: He remains one of just six NFL players to catch 100 or more passes in three seasons in a row.

Marshall earned six Pro Bowl nods committing these feats. The wide receiver did it across seven different teams. The Denver Broncos let him go after that 2009 accomplishment. He’s considered one of the 100 best Chicago Bears players of all time. Marshall left it all on the field.

What happened off the field likely made Marshall an easy target to ship out. He regularly had outbursts of abusive behavior at home and in public, details ESPN. Usually, the charges were dropped, but the initial wave of bad press landed on each organization nonetheless. Until the last few years of his career, he regularly had run-ins with the law. This changed when he realized there was a real source for his seemingly unpredictable behavior.

Why Marshall went public with his Borderline Personality Disorder diagnosis

According to the National Institute of Mental Health, seemingly unpredictable, varying moods mark Borderline Personality Disorder (BPD). Sufferers’ own impulsive actions usually catch them off guard. Outbursts of anger, episodes of depression, or acute anxiety can emerge for hours or days at a time.

It’s called “borderline” because it isn’t any single major mood disorder diagnosis. It’s a cluster of symptoms, making it difficult to pin down. Many people with BPD never receive a diagnosis at all.

Marshall discovered he’d been living with for years. It explained his unstable behavior and sudden swings to feeling out of control, as The Players Tribune details. A simple two-hour therapy session in 2011 changed his world. He saw all the different kinds of people with their own mental illnesses, including personality disorders similar to his. He resolved to use his unique platform, as a nationally-known athlete, to bring awareness to the prevalence of mental illness.

How Marshall fights on behalf of those with mental illness

Athletics had drilled into Marshall that toughness meant stoically pushing through pain, according to the Texas Medical Clinic. But his 2011 diagnosis and treatment showed him that with mental illness, you must communicate. Removing that feeling of isolation with mental distress by reaching out, and learning the art of communication, changed his life.

For fans, the change was obvious. Instead of semi-regular outbursts of violence, or poor decision-making, things went quiet after 2012. Marshall focused on the game. His once-fraught personal life faded into the background, except for his increasing advocacy for people with mental illnesses. He works tirelessly to raise money for mental health awareness, and direct support for disadvantage sufferers.

He appears regularly on his own, the figurehead of his Project 375 foundation. He’s a fixture in public mental health awareness efforts outside his own organization too, reports the University of Michigan. He gave the NFL world performances at WR that broke records, some still untouched. Now, he’s helping millions benefit from his efforts to lower stigma toward PBD, and mental illness struggles in general.