Mario Yamasaki (UFC Referee): Genius, or Lunatic?

You’ve fired up the latest UFC and Bruce Buffer is announcing the fighters. Next, you hear him say: “Our referee for this contest is Mario Yamasaki.”

A thought that is probably going through your mind is, “we might see someone die in this fight.” Mario Yamasaki is a long time UFC referee that has had quite a few ‘questionable moments’ in his career.

He tends to let fights go on quite a bit too long and has gained quite a reputation among UFC audiences: a mostly negative one, unfortunately.

MMA fans know him for his reputation, but they don’t really know who Mario Yamasaki is. I’m going to give you a closer look at who Mario Yamasaki the man is. First, I’ll give you a short bio on Mario, then show you how he got his reputation. We’ll cover his most controversial moments refereeing, UFC fighter’s takes on them, and Dana White’s feelings on him.

Who is Mario Yamasaki?

I guess with the title of this article, the best place to start is telling you, who is Mario Yamasaki?

Mario Yamasaki is a Japanese Brazilian from São Paulo, Brazil. He comes from a family of martial artists. Mario started training Judo as a kid, being taught by his father Shigeru and his uncle Shigueto Yamasaki. Both his father and his uncle impressively hold 8th degree Red/White belts in the martial art.

After training Judo, Mario started learning Jiu Jitsu in 1986 under Marcelo Behring. He would later switch academies and begin training Jiu Jitsu under his brother Fernando Yamasaki. Today, Mario holds a 5th degree black belt in BJJ and a black belt in Judo.

You can critique Mario’s work as a referee, but not as a martial artist. Earning a 5th degree black belt in Jiu Jitsu means that he has dedicated his life to Jiu Jitsu. This isn’t something that is just given out. It is a truly impressive accomplishment for any martial artist.

Mario Yamasaki BJJ Black Belt

The beginning of his UFC career

Yamasaki and his brother started working for the UFC in 1988, helping them organize and promote the first Brazilian UFC event. He was interested in becoming a referee for the organization and approached legendary UFC official ‘Big’ John McCarthy to see if there was an opening. 

The UFC actually were looking to hire new referees and this marked the beginning of Yamasaki’s officiating career in MMA. To this day, he has refereed over 400 fights within all of the major MMA organizations.

Mario Yamasaki is one of the longest tenured and most recognized referees in the sport. Everyone knows him for flashing a heart shape with his hands before every fight that he officiates.

Why is he controversial?

The reason why Mario is a controversial figure in the sport is that he tends to let fights go a bit too long in most fans’ eyes. What I mean by that is he has a tendency to let fighters take a serious beating before stepping in and stopping the fight.

On quite a few occasions in fights Yamasaki has officiated, we have seen fighters sustain damage after losing consciousness. In many cases, a lot more than they really should have taken (in the opinion of experts and fans).

There are quite a few controversial moments in Mario’s reffing career and we’ll cover the major ones.

Yamasaki’s most controversial decisions

Just to give you an idea of some of his controversies, here is a video called “If He Dies, He Dies” that includes some difficult to watch Mario refereeing lowlights:

You probably now understand why some fans have a negative opinion of him.

Derrick Lewis vs Travis Browne

In this fight, Lewis dropped Browne with his patented overhand right. He then started unleashing some vicious ground and pound, putting Browne to sleep. But before Yamasaki stopped the fight, Browne took 5 unanswered right hands, while unconscious.

Rogan Reacts: Derrick Lewis Brutally Knocks Out Travis Browne

This looked really bad, and the shots were unnecessary. Yamasaki could’ve stopped the fight sooner, but chose not to. A definite mistake on his part.

Matt Hughes vs Frank Trigg 2

In a rematch of bitter rivals, Trigg landed a clear low knee to the groin of Matt Hughes. Hughes looked to Yamasaki to pause the fight, but he was out of place on the other side of the cage. He only shouted for Trigg to watch the knees, when he should have right next to them as they grappled.

Trigg then was able to drop Hughes and take his back, almost securing a RNC. Luckily, Hughes was able to persevere and escape to slam Trigg and land an RNC of his own.

In this fight, Hughes pulled off one of the greatest comeback wins in UFC history.But if he didn’t come back and instead Trigg was able to win, it would instead be one of the biggest controversies in UFC history. All due to an error by Yamasaki.

Ovince St Preux vs Mauricio ‘Shogun’ Rua

In this fight, Shogun rushes forward and eats a counter hook from OSP. He is clearly unconscious. Yamasaki is all the way on the other side of the cage, out of place, and rushes in late.

Saint Preux sorprende a Shogun

After he moves in, he doesn’t stop the fight! Instead, he lets Shogun eat 10 to 12 more unanswered shots before stepping in. It was clear the fight was over, but Yamasaki unnecessarily let it go on. This one really could have gotten deadly if it went on for much longer.

Matthew Lopez vs Johnny Eduardo

In this 2017 bantamweight bout, Matthew Lopez finished Johnny Eduardo by strikes in the first round. Lopez landed a total of 38 unanswered strikes before Yamasaki decided to step in and call the fight.

Yamasaki was obviously trying to let Eduardo fight, but it was clear the fight was done halfway through the 38 strikes.

Alistair Overeem vs Travis Browne

Browne was on the bad side of another fight reffed by Yamaski that lasted longer than it should have. After being dropped by a knee to the midsection, Browne did nothing to intelligently defend himself after being badly hurt. He took almost 20 unanswered power shots from Overeem before Yamasaki decided to step in and call the fight.

Valentina Shevchenko vs Priscilla Cachoeira

This was the most lopsided fight in recent memory, and it really should never have been booked. It involved yet another controversy involving ref Mario Yamasaki. From the first second of the fight until Yamasaki decided to stop it in the 2nd, this was a hard fight to watch.

The final stats were 230 landed strikes by Shevchenko to Cachoeira’s 3 strikes. That’s right, Cachoeira was demolished for 1.5 rounds and landed 3 strikes, while absorbing 230 strikes.

Yamasaki was at fault for letting this fight go on. Cachoeira got abused. But Yamasaki wasn’t the only one to receive blame, as Cachoeria’s corner was chided for not protecting her. The Brazilian commission that booked this fight also should’ve never let a debuter get in the ring with a championship caliber fighter like Valentina Shevchenko.

Kevin Lee vs Michael Chiesa 

The last fight I’ll mention is an unusual controversially early stoppage by Yamasaki.

Kevin Lee took Michael Chiesa’s back and sunk in a rear naked choke. Chiesa put his arms down and was seemingly not defending the choke, so Yamasaki stepped in and stopped the fight. Michael quickly popped up and protested the stoppage. He claimed that he was tensing up his neck and trying to last the final seconds of the round.

Normal protocols for refs are to ask if a fighter is okay and check if they’re conscious before stepping in. Mario assumed that when Chiesa dropped his arms he was out cold, and seconds later we had another Yamasaki controversy.

Fight comments on Yamasaki

There is a long list of fighters that have made unfavorable comments towards Yamasaki following matches he officiated. To keep it short, I’ll stick to some comments made by fighters during the infamous Shevchenko vs Cachoeira fight.

Former lightweight champ RDA chimed in after watching the one sided fight with this comment.

Gilbert Burns was pretty blunt in his thoughts about Yamasaki’s officiating.

Kenny Florian wasn’t afraid to voice his opinion on the bad officiating either.

I could show you 20 or 30 more comments from pissed off fighters, including Mike Chiesa challenging Yamasaki to a BJJ match. But I think you get the idea – some fighters have strong feelings about Yamasaki’s work.

Dana White Bars Yamasaki From UFC Events

Dana White is not one to mince words about bad officiating. He has been super critical of questionable referees like Steve Mazzagatti, and especially Mario Yamasaki. What really set Dana off was Yamasaki’s comments defending his decision not to stop the Shevchenko/Cachoeira fight.

The way I see it, I allowed ‘Pedrita’ to be a warrior and keep fighting. I could have stopped the fight in the second crucifix or mount, but she was moving all of the time.

– Mario Yamasaki

After hearing these comments, Dana immediately fired back on the UFC post fight show with Kenny Florian and Michael Bisping, saying, “I think it’s disgusting and I think he’s disgusting and I never want to see him ref again!”

He continued to tear into Yamasaki’s comments: “for that idiot to say she fought like a warrior, no you moron and he makes me sick. That guy has no business reffing fights. And I promise you, you’re never going to see him again.”

Since that fight, we have not seen Mario Yamasaki ref another fight in the UFC. This begs the question: is Mario Yamasaki a bad ref, and does he deserve to ref in the UFC again?

Most of the time he has been a good official. He has worked over 400 MMA fights in over 20 years of being a referee. More times than not, he did a good job… but at the same time he has made some horrible decisions.

I understand Mario Yamasaki like to give fighters a chance to “be warriors,” but his job is to protect them. Yamasaki deserves respect as a martial artist and for his tenure as an official, but his bad fight night decisions rightfully deserve some criticism. 

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