Amazing story, if true (and I'm assuming it is). From the Daily Mail:
Having shot and tracked the bear for about a mile while out hunting deer, Mr Machado admitted making the near fatal mistake of relinquishing his rifle after finding its body deathly still.
The bear lunged.
Jumping behind a tree for protection, Mr Machado said he pulled out his hunting knives and desperately swiped them at the bear who retaliated by knocking them aside.
Hoping to scare the bear away, Mr Shinn fired a warning shot in the air which had no effect on the attack.
Instead, the bear bit down onto Mr Machado's arm.
'It just latched on. I just started screaming,' he said.
Reeling, Mr Machado managed to release his arm from the bear's mouth just before it latched onto him again inside his upper thigh.
Dramatically pulling away, both the man and beast tumbled down a 50-foot embankment before Mr Machado hit the ground, with the bear landing across his chest.
That's when he said his former high school wrestling skills came in handy.
Wrapping his arms around the bear's neck in a headlock, 'just squeezing as hard as I could,' he screamed for his friend to shoot.
Pulling the trigger, Mr Shinn was in a momentary flash of panic with his gun this time failing to fire.
Grabbing Mr Machado's rifle, he tried again, firing and making the life-saving shot.
He felt the bear go limp in his arms, heard its final breath.