Sources at Lovelock Correctional Center in Nevada tell TMZ, reports of Simpson being beaten to a "bloody pulp" during a prison yard fight were so ridiculous, guards pulled O.J. from his cell ... just to tell him about the crazy rumors.
Simpson found the mass confusion incredibly entertaining -- in fact, we're told he "laughed his ass off" at reports of the racially-motivated prison attack.
For the record -- an official rep for the prison tells us, there have been "no incidents regarding O.J. in any shape or form." Finally, a clean slate.