You could be forgiven for assuming that super-rich professional baseball players don't need a labor union as much as, say, early 20th-century coal miners. After all, ballplayers' salaries are astronomical, and their lives embarrassingly cushy. But it wasn't always that way.

Baseball players — even stars — used to struggle. Their comfort today comes from the strength of their labor union, which is the most formidable in all of professional sports. If hockey players had a union as strong as baseball, the NHL wouldn't be suffering its third lockout in 20 years.

Two men are primarily responsible for MLB's labor strength: Marvin Miller and Donald Fehr. The first reformed the Major League Baseball Players Association into a union. The second, as head of the MLBPA, fought cases against the league as it tried to regain control. Together, they put into place ways to protect players against the league's gold-plated antitrust exemption.

In 1922, the Supreme Court ruled that Major League Baseball was exempt from antitrust laws. No other sports league has been granted that exemption. This essentially ended all other rival leagues, like the Federal League, which had competed against MLB in the mid-1910s. Thanks to SCOTUS, if you wanted to play baseball professionally, you had to work for MLB. The league had a monopoly, and faced absolutely no competitive pressure to raise player salaries or offer comprehensive benefits. As a result, teams often paid players peanuts.

Fast forward to 1966. The MLBPA appointed Marvin Miller as its executive director. That year, the annual league minimum wage was $6,000, and the average player earned $19,000. Not exactly a king's ransom. Miller, who had spent his career working in labor unions, instilled in players a lesson: Without them, the owners had no game. Players provided far more value than their rather paltry compensation suggested.

Miller led a crusade against the owners, and helped eliminate the reserve clause, which gave owners control in perpetuity over player contracts. He also helped institute free agency, which allowed players to solicit contracts from other teams.

In less than two decades at the helm, Miller changed labor rights in professional baseball. When he left in 1982, the average salary was $241,000, and baseball players had a say in their future.

In 1985, Donald Fehr was appointed the players association's executive director. In 1994, with player salaries continuing to rise thanks in large part to Miller's revolution, ownership proposed a revenue-sharing model that would enforce a player salary cap and force big-market teams to share profits with smaller-market teams. The players said no, and the league withheld pay. In August, players began a 232-day strike, costing baseball the 1994 World Series and delaying the start of the 1995 season. It was a hugely risky power play in which the league tried to regain some of the ground it had lost while Miller was in charge. But Fehr wouldn't budge an inch.

Some diehard baseball fans still blame Fehr's stubbornness for the loss of the 1994 World Series, but for those sympathetic to the union's struggle to establish itself, Fehr was a champion. He understood that yielding to the league would set a hugely damaging precedent for the union, so he made it clear to MLB that, even without Miller at the helm, the MLBPA was an aggressive and capable force to be reckoned with.

Fans understandably have trouble sympathizing with players-versus-owners labor disputes; after all, it's typically millionairres versus billionaires. But we have to keep in mind that it wasn't always this way, and without a strong union, we could see a huge regression. Imagine if you got a job right out of college, and your employer owned the rights to your services forever. You couldn't leave and get a similar job elsewhere. Crazy, right? But that's how Major League Baseball used to operate. Only because of baseball's labor union do players now have a choice in where they end up. Before 1966, when Miller took over the MLBPA, teams set the price they would pay players, and that was that. There was no bargaining. Today, the union empowers the best players to compete for the best contracts; the better you play, the better you're paid. Of course, teams now outbid each other — often rabidly and irrationally — in pursuit of highly desired free agents. But isn't that better than no free agency at all?