Slap fighting: The next big thing, or unsporting stupidity?

In this photo provided by Zuffa LLC, Azael Rodriguez slaps Jesus Gaspar at a Power Slap event in Rio De Janiero, Brazil, Nov. 30, 2022. The competitors stand rigidly upright with their hands behind their backs, waiting to absorb a brutal slap to the face. (Mike Roach/Sciaffo LLC via AP)

In this photo provided by Zuffa LLC, Ryan Phillips slaps Rob Perez at a Power Slap event in Las Vegas, March 31, 2022. When the open-handed blow is delivered, there's a sharp report and the reaction can be dramatic. Some fighters barely move, while others stumble backward or fall to the floor. Some are knocked out. (Chris Unger/Zuffa LLC via AP)

LAS VEGAS — The competitors stand rigidly upright with their hands behind their backs, waiting to absorb a brutal slap to the face.