With UFC 145 only two days away, Jon Jones' opponent for that event, Rashad Evans, may not want to check this clip out. Taken from the documentary, "The Proven Grounds," Jones is training while receiving some instructions outside of the Octagon when all of a sudden, Bones knocks out his sparring partner with one punch! The UFC Light Heavyweight Champion immediately takes a knee to see how the poor guy is doing, but Jon's coach wasn't having any of that. "You gotta finish the round," his coach says. Now, the next victim, er, sparring partner is brought in to receive some punishment...with the KO'd dude still laid out right next to them! That mixed martial arts is a cutthroat business.    

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[via Boxden]

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