Under Major League Baseball’s new anti-hazing rule, Superman is still OK, but Wonder Woman is now a no-no.

According to MLB’s new rule — the details of which were made public for the first time Monday night — rookies won’t be forced to wear dresses anymore as part of their club’s annual rookie dress-up day. Nor will they be forced to dress up as female superheroes.

The rituals have been around baseball for years, but the league’s new collective bargaining agreement installs a new anti-hazing, anti-bullying policy that outlaws the practice.

Oakland A's players in dress-up mode, circa 2008. (AP) More

According to Ronald Blum of the AP:

The policy, obtained by The Associated Press, prohibits “requiring, coercing or encouraging” players from “dressing up as women or wearing costumes that may be offensive to individuals based on their race, sex, nationality, age, sexual orientation, gender identify or other characteristic.” MLB Vice President Paul Mifsud said Monday the new rules resulted partly “in light of social media, which in our view sort of unfortunately publicized a lot of the dressing up of the players … those kind of things which in our view were insensitive and potentially offensive to a number of groups.” “There’s lots of pictures of baseball players dressed up as Disney princesses,” he said.

That there are. This past season, to name a few, the Los Angeles Dodgers had their rookies dress up as cheerleaders and the Atlanta Braves rookies dressed like the Rockford Peaches from “A League of Their Own.” But that’s not the exclusive purpose of rookie dress-up day. Players also dress up as cartoon characters or superheroes or in wrestling singlets, like the Tampa Bay Rays.









Tradition continues—the #Rays rookies are wearing their Team USA-inspired singlets for the flight to Toronto. pic.twitter.com/EskRF1Gbm2 — Tampa Bay Rays (@RaysBaseball) September 11, 2016





The debate on this topic has raged for years, with some saying it’s harmless fun and a rite of passage, while others saying that rite of passage can exist without the subtext that looking like a woman is embarrassing.

The language new rule says, according to the Associated Press: “The purpose of this policy is not to prohibit all traditions regarding rookies or players, but rather to prohibit conduct that may cause players physical anguish or harm, may be offensive to some players, club staff or fans, or are distracting to the operation of the club or MLB.”

Under that, some forms of hazing are still fine: Like the tradition some clubs have of sending rookies on a coffee run in full uniform or forcing rookie relievers to carry the bullpen bag.

In a more extreme recent case that has nothing to do with dresses: Texas Rangers minor leaguers were sent to psychological counseling after a hazing incident in which they held down a 16-year-old teammate and masturbated him.

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Mike Oz is the editor of Big League Stew on Yahoo Sports. Have a tip? Email him at mikeozstew@yahoo.com or follow him on Twitter! Follow @MikeOz