Hulk Hogan Put 3 Guys In Hospital During 'Rocky III' ... Says Sly Stallone

Hulk Hogan was such a violent beast as Thunderlips on the set of "Rocky III" ... he accidentally put 3 GUYS in the hospital during the filming of his famous boxing ring brawl with the Italian Stallion.

Stallone has finally revealed the crazy story 35 YEARS after the movie hit theaters ... describing how a young actor named Terry Bollea (6'7", 295 pounds with 24" biceps) didn't know his own strength!

"I remember a violent move where he threw me into the corner , charged across the ring like an ENRAGED bull and leaped so amazingly high Above me,that his shinbone actually came down giant tree on my collarbone , and I tumbled to the floor," Stallone said in an Instagram post.

"I was afraid to look at my shoulder for about 10 minutes ... I said "don't roll me over , don't move me, " because I was sure there was bone protruding through my upper chest!"

That's when Stallone brought up the poor guys who really did suffer injuries ...

"Believe it or not when he jumped into the audience to fight with the stuntmen , three of them had to be treated at the hospital."

Stallone concluded with a message to his old co-star:

"HULK , if you're reading this, it was a privilege to be mangled by such a gentleman."