Video of Michael Phelps Crowd Surfing Accident Goes Online
Phelps -- who's STILL in party mode after the London Games -- hit up XS nightclub Monday night, and for some reason thought it would be a good idea to crowd surf inside an inflatable raft.
It was not ... because the 18-time gold medalist barely made it a few feet before toppling backwards onto his rear end.
Thankfully, we're told he was okay. Check it out.
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