Frank Mir has recalled how a training session with a former UFC star almost ended in disaster, with tensions erupting on the mat.
The former heavyweight world champion has formidable Brazilian jiu-jitsu skills, with his fearsome submissions almost resulting in a nightmare scenario.

Frank Mir went out of his way to teach Jason Miller a lesson
Frank Mir is simply one of the scariest practitioners to have ever graced the octagon. With a deadly ground game, the legend has compiled an excellent resume, featuring Tim Sylvia and Antonio Rodrigo Nogueira, whose arms he broke when they refused to tap.
To put it simply, if you refuse to submit against Mir, whether it’s on fight night, or in the gym, he’s more than happy to inflict whatever physical pain is necessary to get the job done.
In an interview on the JAXXON Podcast, he said: “If you’re one of those guys that just doesn’t want to tap, don’t train with me, because I’m going to f**k you up.”
With that in mind, the heavyweight legend and Jason ‘Mayhem’ Miller grappling together, was a recipe for disaster.
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Mir explained: “We were training at Marc Laimon’s, and Laimon said, ‘Hey, Frank, practice is over … once you finish somebody.’ So then, I just went through and turned it on, and started tapping everybody.
“So then, I had Mayhem, and I put him in a guillotine, and he almost killed himself. He ran his feet up the f*cking cage, and almost tried to flip over the top of me. It was weird.
“So then, I let it go, and then I got him in a kimura, and I applied it. I started going and cranking it, and I was like, ‘I ain’t letting go. F*ck this. Today you’re going to learn!’ So I put his hand to the back of his head.”
Frank Mir reveals the hardest puncher he’s ever faced
In his esteemed career, Mir has entered the cage with some of the most fearsome men to have ever walked the face of the Earth.
With a willingness to walk into the fire, the American has taken punches from the likes of Brock Lesnar and Mark Hunt.
However, the 45-year-old claims neither of those men is the heaviest puncher he’s ever faced.
Mir opened up about the one fighter who hit him harder than anyone else.
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