Professional wrestling was much like professional boxing in the late 19th/early 20th century. It was a legitimate sport, but lots of matches were fixed. See, they didn't have big sports arenas or stadiums like we have now where they could draw a huge audience and make money off of ticket sales, wrestlers and promoters made money betting on the matches. And you can make a lot more money betting when you can control the outcome. So wrestling had "worked matches" in the same sense that boxing had "fixed fights." Since it requires no balls or bats, logic would tell you that wrestling is the oldest sport in the world, but professional wrestling was never entirely on the level.

Of course, people figured out that there was something off about the wrestling business. You can find all kinds of exposes in newspapers of the period. How do you keep making money when the marks are on it?

Enter wrestler/promoter Joseph "Toots" Mondt, who is credited with the idea of making professional wrestling, as you describe it, a stage show. Mondt called it "Slam Bang Western Style Wrestling." This would have been in the 1920s, when Mondt and his partners Billy Sandow and Ed "Strangler" Lewis - collectively known as the Gold Dust Trio - took over the wrestling business.

Why didn't this happen to other sports? Well, it did. Watch a UFC card. The fights aren't worked, but there are still bright lights, entrance music, and ring girls in skimpy outfits. The same is true of boxing. I'm not a sports person, but I've seen enough football, baseball, basketball, and hockey clips to know that they've all adapted stage show aspects from professional wrestling.

For more on how pro wrestling became pro wrestling, check out the new annotated edition of the 1930s wrestling expose, The Fall Guys.