On Friday night at the Cosmopolitan in Las Vegas, Dayne “Da Hawaiian Hitman” Viernes will just have to stand there — not moving, chin up, hands behind his back — as Makini “Big Mak” Manu, a fearsome 390-pound behemoth, strikes him in the head as hard as he can with an open hand.
Viernes, a 33-year-old, 6-foot-2 powerhouse, will have 60 seconds to recover — presuming he doesn’t lose consciousness — and return the favor to Manu, 32.
The two men will continue alternating giving and receiving brutal blows until one of them passes out or is declared the winner of Power Slap.
The brainchild of Ultimate Fighting Championship (UFC) impresario Dana White, Power Slap was first launched in 2023 and has become the most prominent organization for a brutal combat sport known as slap fighting. It’s part of a rash of disturbing, ultra-violent spectacles that are gaining in popularity — with potentially dire consequences.
“We’re creating a new generation of athletes with post-concussion syndrome and chronic traumatic encephalopathy (CTE) who simply aren’t paid enough to cover their long-term care,” said Dr. Christopher Nowinski, a neuroscientist and researcher into CTE. “We’ll pay for it as a society for another 70 years by having to care for people with more mental health problems and dementia.”
The Post has reached out to White for comment. In the past, he’s been quick to deflect criticism and boast about Power Slap’s popularity.
“People love it,” he has enthused. “The numbers don’t lie.”
Indeed, Power Slap draws one billion views per month across social platforms and has nearly four million subscribers on YouTube and almost fourteen million followers across Instagram and TikTok.
Power Slap bouts typically last between three and five slaps per fighter, although they often end much earlier as participants struggle to recover from the impact. The winner is declared by knockout, technical knockout or a judge’s decision based on the power, accuracy and force of blows.
The inaugural event in Vegas in 2023 saw contestants suffer a range of injuries, from bloodied lips and black eyes to memory loss and unconsciousness. Medical experts suggested that some opponents exhibited clear signs of Stage 3 concussion and traumatic brain injury (TBI).
It’s enough to make the head injuries suffered by boxers, football players and even MMA fighters seem quaint.
A 2025 study in the Journals of the American Medical Association (JAMA) analyzed 78 slap fights and found that nearly 79% of competitors exhibited signs of concussion after being slapped, many of whom then returned to be slapped again.
In 2021, Polish slap fighter Artur Walczak was knocked out in a PunchDown event — a competition similar to Power Slap — in Warsaw, Poland. He suffered severe bleeding on the brain, and spent a month in hospital in a medically-induced coma before passing away.
While boxing – “the original brain damage sport” according to Nowinski – has long had its critics, it differs from slap fighting in that participants can bob, weave and dodge potential blows. MMA and Ultimate Fighting also allow fighters to defend themselves. In Power Slap, competitors must passively stand and receive blows when it’s their turn to be hit.
Nowinski says its popularity shows that we’re becoming increasingly desensitized to violence. “In nearly all cases, CTE is caused by culturally accepted voluntary sports participation and many of these sports wouldn’t have been culturally acceptable a decade ago,” he said.
Other barbaric gladiator sports are also on the rise.
In 2018, Wyoming became the first state in US to legalize bare-knuckle boxing. Last year, there were no less than 65 events for the bloody sport, which not only eschews gloves but also has fighters in a ring half the size to up the intensity.
Lethwei, a Burmese style of bare-knuckle boxing that allows headbutts and is considered one of the most brutal forms of martial arts, is also gaining in popularity.
A new amusement, the Run It Championship (RNC), takes the idea of a tackle in football or rugby and makes it into a standalone event all of its own.
Launched in Australia in 2025, it sees two hulking men, without protective padding, stand at either end of an indoor 60-foot runway. One carries a football under his arm, and, when the signal is given, the two sprint headlong into each other, colliding in the middle at maximum speed and impact.
Like Power Slap, it’s perfectly suited for social media with short, shocking clips drawing tens of millions of views.
Nowinski said RNC’s popularity is another worrying development.
“Its tacit minimization and endorsement of brain injury sends young people a message that can only hurt them in the future,” he said. “It’s really disappointing.”
He’s also discouraged by the fact that Power Slap was officially approved by the Nevada State Athletic Commission in October 2022, ahead of its launch.
“There was a brief opportunity to stop these sports from becoming profitable enough to be sustainable,” he said. “But now that the dam has broken.”
Meanwhile White believers haters should just stay out of the ring — and the audience — and not worry about the broader societal impacts of CTE.
“If you don’t f—— like it, don’t watch it!,” he said in 2023. “Oh, you’re disgusted by it? Watch ‘The Voice.’”
