Michael Bisping briefly came out of retirement Saturday night, choking Steve-O unconscious in a UFC Octagon ... while the Jackass star refused to tap!
It all went down at the UFC APEX Center on Saturday in Las Vegas. Steve-O was in the building to watch the UFC Fight Night card ... but got in on the action himself after all of the fights were settled.
The clip starts with 44-year-old Bisping standing behind Steve-O, and he has him in a rear naked choke. Michael applies pressure ... and after 11-12 seconds, and a refusal to tap out, Steve-O went to sleep.
Bisping, former Middleweight champion (although not known for his submissions), then laid Steve-O down on the canvas while everyone waited for him to wake up.
After a few seconds, Steve-O popped his head up and said ... "Oh s***!", as everyone cracked up.
Bisping told Steve-O ... "You crazy bastard. Are you okay?!"
Of course, as scary as Bisping is, this isn't even close to the craziest thing Steve-O has done on camera ... the man has been hit, bit, and everything else during his crazy career!