It was the thump heard round the world: While performing at the Billboard Awards, singer Miguel jumped over the crowd, only to kick someone's head when he landed -- someone who may now have brain damage.

Now word is leaking that Miguel was ordered by show organizers not to attempt that jump in the first place.

At the time of the accident, Miguel said the jump was a spur-of-the-moment thing, but sources close to the Billboard Awards producers tell TMZ that's not true. Seems Miguel approached the showrunners during rehearsals and asked if he could make that fateful leap -- and was turned down for reasons of safety.

But he did it anyway and then blamed it on rock n' roll, tweeting the since-deleted hashtag "Rockandrollmademedoit" and telling his fans in an also-axed comment, "got caught up in the moment, thank goodness [the victim] is okay."

Except, you know, she may not be. But if (or, more likely, when) there's a lawsuit, sounds like show producers want to make sure they aren't named as defendants.