He’s the answer to multiple trivia questions. Who was the only rookie to start in the 1977 World Series? Who invented the high-five? And who was the first Gay Major League Baseball player—to our knowledge—to be out of the closet in the presence of his teammates, if not the fans? The answer to all these questions in Glenn Burke, the subject of a brilliant new documentary, OUT: The Glenn Burke Story (debuting November 10 on Comcast Bay Area, DirecTV’s sports pack channel 696 and Dish Network’s multi-sports package channel 419). In a year of stellar sports documentaries—thanks largely to ESPN’s consistently strong thirty-for-thirty series—OUT is the best I’ve seen. What sets it apart is that it does more than explore an athletic hidden history. It speaks to today’s sports world about the stubborn endurance of the closet in the men’s locker room over the last thirty years.When thinking about LGBT athletes and what they’ve faced, people are very familiar with female jocks like tennis legend Martina Navratilova and basketball star Sheryl Swoopes. Maybe they also know male athletes who in recent years have come out after retirement like NFL player Esera Tuaolo and NBA center John Amaechi. But in Burke we have a story that hasn’t been told, and demands an audience. In the able hands of producer Doug Harris, we learn about an athlete who was more than just a two-sport Oakland Area legend, playing both baseball and hoops with pro potential. He was also a young man, growing up in the Bay, and confident about his sexuality. That confidence, for anyone, was rare back then, but to find it in a male star athlete is remarkable.

As OUT tells us, Glenn’s confidence was put to the test when he made the big leagues. Dodgers teammates like Dusty Baker, Davey Lopes, Reggie Smith, Rick Monday and Manny Mota, tell the story of a player whose sexuality was noticed, recognized and even accepted by some teammates but looked on with horror by management. After all, when you wear a red jockstrap in the locker room, people will start to talk. The story where the Dodgers organization offered Glenn $75,000 to get married is particularly gob-smacking. Later when Glenn was traded to Oakland, the pressures intensified. Former Burke teammate Claudell Washington tells this anecdote in OUT: “[A’s Manager Billy Martin] was introducing all the [new] players and then he got to Glenn and said, ‘Oh, by the way, this is Glenn Burke and he’s a faggot.’” By 1980, Glenn was out of the game but the story doesn’t end there. OUT then tells the story of Glenn’s life after baseball: triumphantly coming out to Sport magazine and Bryant Gumbel on The Today Show; participating in the first Gay Games in 1982, and being a public figure in the San Francisco scene. But then Glenn’s life took a tragic turn as drugs, petty crime and the AIDS epidemic claimed his life. He died in 1995 at the too-young age of 42.

The grand unanswered question that hangs over the documentary is how good could Glenn Burke have been without the relentless pressures of homophobia? To hear Dusty Baker tell it, he could have been truly great. OUT is a must see for anyone who cares about LGBT rights and finally conquering what is in many ways the final frontier of homophobia in our society: the men’s locker room. If anything, by the documentary’s end I felt a sense of deep regret. I regretted that I wasn’t more familiar with Glenn Burke’s story. I regretted that I didn’t have an entire section on his life in my book A People’s History of Sports in the United States. I regretted that this hidden history has been shunted back so deeply in the athletic closet, it’s largely unknown. We owe Doug Harris and the entire team that produced, directed, wrote and researched OUT a tremendous debt. This is the kind of special documentary filmmaking that has the power to change lives. Every high school sports team in the country should watch this remarkable work so the next generation’s Glenn Burke can exist out of the closet and not out of the game.