Caution: Infamous Referee Mario Yamasaki is Back in the Cage in 2026
Ladies and gentlemen, this is not a drill. Please use caution: Mario Yamasaki is back in the Octagon officiating high-level fights.
Mario Yamasaki: The Good
The much-maligned referee was tasked with being the third man in the cage on Saturday in Washington, D.C., where Thad Jean defended his title against Ernesto Rodriguez. Let’s give credit where it’s due: Yamasaki did a fantastic job. Jean and Rodriguez went to war, with each producing sequences that could have ended the fight. Yamasaki correctly allowed the action to continue until Rodriguez stopped intelligently defending himself from Jean’s ground-and-pound in Round 3.
To be fair to Mario Yamasaki, he is not the most hated referee in the history of combat sports. That title belongs to Steve Mazzagatti. However, Mario is definitive number two on the worst referees ranking. Yamasaki worked as a referee in the UFC from 1999 to 2018, the second-longest tenure of any MMA referee behind only “Big” John McCarthy.
Unfortunately for Mario, he became infamous in the MMA history books. During parts of the 2010s, it felt like nearly every fight he officiated ended in controversy.
Mario Yamasaki: The Bad
There was the infamous 2012 fight in which Yamasaki took a win away from rising contender Erick Silva with an eyebrow-raising decision. Silva knocked down Carlo Prater and went in for the finish with ground strikes. What seemed like a clear victory was overturned to a disqualification after Yamasaki claimed Silva had landed illegal shots to the back of the head. Replays showed that most of the strikes were clean. It was also shocking that Yamasaki went straight to a DQ rather than restarting the fight and possibly deducting a point. The call was so controversial that Joe Rogan interviewed Yamasaki in the cage afterward and made him watch the replay of the stoppage live.
And then there was the Donald Cerrone vs. Alex Oliveira fight, where Oliveira had to tap repeatedly to a triangle choke before Yamasaki finally stopped the bout. On the other side of the spectrum, Yamasaki once stopped a fight between Michael Chiesa and Kevin Lee while Chiesa was clearly still conscious.
Mario Yamasaki: The Ugly
However, the moment that seemed to define his career came in 2018. Valentina Shevchenko, after losing to Amanda Nunes for the UFC bantamweight title, moved down to the newly created flyweight division. Instead of putting Shevchenko directly into a title fight at 125 pounds, the UFC booked her against debuting fighter Priscila Cachoeira in what was essentially a tune-up matchup.
The fight was a complete mismatch from the opening bell. Shevchenko landed an astonishing 230 strikes while a bloodied Cachoeira managed only three. Yamasaki repeatedly declined to stop the fight despite the overwhelming damage being inflicted. Shevchenko ultimately had to take matters into her own hands, securing a rear-naked choke to end the brutal beating.
Yamasaki’s performance that night was widely condemned, but he made matters worse by saying afterward that he wanted to “let Cachoeira be a warrior.” An outraged Dana White immediately told the media that Yamasaki would never referee in the UFC again. Of course, the UFC does not actually select its referees; athletic commissions do, so White had no direct authority to fire him.
Don’t just take my word for it. LowKickMMA wrote an article, showing Yamasaki’s seven worst moments back in 2018, following that fight.
Mario Yamasaki Returns
After that, Yamasaki largely disappeared from major MMA events. In 2023, rumors began circulating that he would return as a referee under the Washington, D.C., Athletic Commission. Since then, he has worked regional shows here and there, but he had not been assigned to a major fight.
That changed on Saturday when Yamasaki stood in the cage for a PFL main event. As of now, it appears he is licensed to referee only in Washington, D.C. It will be fascinating to see whether he receives more assignments and whether a UFC return is possible eight years after Dana White publicly declared him done with the promotion.
For the sake of everyone involved, let’s hope Yamasaki continues to perform well. There is no benefit in rooting for a referee to fail. But even with a strong performance, there will always be a certain level of anxiety among MMA fans whenever they see Mario Yamasaki standing in the cage.
