Just in case you didn’t know, Mixed Martial Arts is a dangerous sport. The goal of the entire sport is to incapacitate your opponent through a combination of punches, kicks, knees, elbows and submission holds. Now while every fight doesn’t end in a crushing knockout or a suffocating submission, nearly every fighter takes some form of damage to his or her head. The more we learn about concussions and brain damage, the more insane it seems that some fighters have stayed so long in this deadly game while rarely or even never staring back into a doctor’s flashlight. MMA may be a tough guy sport, but there are some who stand head and shoulders above their peers with their ability to take punishment and keep going.

This list will honour those who have taken nuclear warheads of strikes to the dome and have somehow kept going without slowing down. This list will focus specifically on how these fighters are able to deal with head strikes. Their overall ability to take damage (which would include leg and body strikes) will not be taken into account. That will explain how some fighters with (T)KO losses by non-head strikes can still be eligible for the list.

These rankings also only include fighters who have fought in the UFC, which excludes the legendary Fedor Emelianenko from the list. Emelianenko fought his best fights in the defunct PRIDE organization, where he won their Heavyweight championship in 2003 and bested knockout artists like Mirko Cro Cop and Mark Hunt along the way. His chin certainly was worthy of his legend status, but ultimately is knocked off the list.

A final note on the list is the competition faced by the fighters. It is one to survive strikes from scrubs on the regional scene, but its quite another to walk through shots from UFC champions.

10 10. Brian Ebersole

One of the oddest characters in MMA, Brian Ebersole kicks off the list. While it is highly disputed whether or not his chest hair is the source of his power, there are quite a few incredible facts about Ebersole. He has fought in the highest number of fights out of any fighter on the current UFC roster, with an astounding record of 51-16-1 and one no contest. Want to know what’s even more incredible? He has not been knocked out in any one of those fights! What brings Ebersole down on the list is that the majority of his fights have taken place outside of the UFC. If Ebersole had made the trip to the UFC earlier in his career he would have shot up this list but as it stands, he sits at number 10.

9 9. Patrick Cote

The owner of an amazing first name and a stone crushing right hand, the Quebec native has quite the ability to eat punches, which is super helpful when you’re not exactly known for your technical acumen. The Predator fought at both middleweight and welterweight and nobody at either weight class has been able to officially knock him out. Cote has been knocked out but only due to illegal strikes from Alessio Sakara at UFC 158, a fight which Cote won by disqualification. The only official TKO loss on his record is due to tearing his ACL in a fight versus Anderson Silva at UFC 90. Like Ebersole, Cote’s low ranking is due to not facing many killers as other higher ranked fighters.

8 8. Frankie Edgar

If you are often seen as the real life incarnation of Rocky Balboa, you better have one hell of a chin to live up to that billing. Luckily for him, “The Answer” Frankie Edgar channels the Italian Stallion’s ability to handle punishment like a natural. The former UFC Lightweight champion has faced a murderer’s row of foes, which include B.J. Penn, Jose Aldo and Gray Maynard, all of which have failed to knock Edgar out. Edgar, possibly more than any other on this list, has come the closest to being knocked out without actually going out in his second and third fights with Gray Maynard. He has come close, but the complete lack of knockout losses is impressive. By the time Edgar hangs up the gloves, it’s possible that he jumps to the top of this list.

7 7. Carlos Condit

Many fighters claim to be Muay Thai fighters, but this Natural Born Killer might have the most varied striking arsenal in MMA. Equally using all eight points of legal striking, Carlos Condit has been waging war in the cage since 2002 while also dabbling in some pro boxing and kickboxing in the meantime. In all three combat sports, Condit has only two (T)KO losses, one due to leg kicks from kickboxing extradonaire Andy Souwer and the other coming from a torn ACL suffered against the monstrous Tyron Woodley. Coming out of wars with Jonny Hendricks and Martin Kampmann while staying on his feet is a great feat for the New Mexico warrior and that lands him at number seven on this list.

6 6. Junior Dos Santos

In a world without Cain Velasquez, Junior Dos Santos would likely be the baddest man on the planet as the UFC Heavyweight champion. Cigano has tremendous takedown defense, great offensive boxing and a skull so durable Wolverine is looking to coat his bones in Dos Santos’ DNA. Competing in heavyweight division is a good way to get knocked out but by some miracle Dos Santos has only one TKO loss on his record, which was more of a mercy killing after Cain Velaquez had beaten his head for 10 rounds straight. The beatings that JDS has suffered have been so horrifying that some are questioning how much longer he can keep surviving these wars. If his performance vs Stipe Miocic at UFC on FOX 13 is any indication, Junior Dos Santos has a long way to go before being stopped.

5 5. Chris Lytle

Fireman, politician and mixed martial artist Chris Lytle has worn many hats but will be remembered by most people for being one of the most exciting fighters in MMA history. Perhaps even more notable than his captivating brawls is his ability to take just as much damage as he dishes out. In 69 MMA and boxing matches, Lytle was never submitted or knocked out. Not a single time. There was a reason why Lytle had so much fan support despite never receiving a UFC title shot. His mindset of taking two shots to land one of his own endeared himself to legions of fans and his solid chin lands him at number five.

4 4. Roy Nelson

For a fat guy, “Big Country” can certainly go toe to toe with the best of them. Toe to toe being literal in this case as it seems to take an atomic blast to put Nelson down on the canvas. Don’t let his two knockout losses fool you; Nelson competes in the hardest hitting division and regularly walks through strikes which would knock out 99% of the world’s population. From the whooping he endured from Junior Dos Santos and the brutal knees he ate from Fabricio Werdum at UFC 143, Nelson is no doubt one of the toughest men walking the planet.

3 3. Dan Henderson

When you’ve been in the mixed martial arts game as long as Dan Henderson has, you’re bound to run into some incredible fighters who are capable of putting you down in an instant. At the age of 44, Dan Henderson is still one of the most dangerous men in the light heavyweight and middleweight divisions. Henderson has had to face some killers to earn the reputation he now enjoys though. Men like Anderson Silva, Wanderlei Silva, Lyoto Machida and Mauricio “Shogun” Rua have all tried to knock Hendo out and all were unsuccessful. A TRT-fueled Vitor Belfort was the first to finally KO Henderson back at UFC Fight Night 32 with a head kick but it took 16 years for someone to pull off that feat. As Henderson’s career winds down, his chin will stand the test of time as one of the best ever.

2 2. Diego Sanchez

For all its criticism and reality show shenanigans, the Ultimate Fighter has produced some of the toughest fighters in the history of the sport. None though have matched the ruthless intensity and unshakeable will embodied by Diego “The Dream” Sanchez. Far from the most talented fighter on this list, Sanchez has gone from a one-time title contender to a man whose last three wins have come under disputed decisions. Despite the drop off in skill, Sanchez still demands the respect of MMA fans due to his iron jaw. In almost every fight he takes dozens of concussive blows but through some stroke of luck he has not been knocked out. The amount of punishment he’s taken from B.J. Penn, Martin Kampmann, Gilbert Melendez and several others have probably years off of Sanchez’ life but it does nab him the number two ranking on this list.

1 1. B.J. Penn

A legend in every sense of the word, “The Prodigy” B.J. Penn has a legacy that none can touch. One of two men to hold a UFC championship in two different weight classes, Penn retired this year as one of the most naturally gifted athletes in MMA history. But if you were to strip away all of his skill, you would still be left with the greatest chin of all time. Penn has taken beatings from some of the best names across five weight classes without ever being truly knocked out. His TKO loss to Matt Hughes seemed like he was more tired than hurt and his loss to Georges St-Pierre came out of a corner stoppage, not because of Penn’s lack of willpower. With his only TKO losses coming from the best in the world, it’s hard to argue that Penn has ever been truly knocked out. Penn may have exited MMA on a sour note, but his status as the toughest man in UFC history will never be questioned.