Rocky Marciano was a Professional Boxer. He is known for his career record: 49-0-0 43KO.  Regardless of the critics, Rocky Marciano fought an era of tough Competition, and was hard to hit., and he was relentless as a fighter.
"What's so often forgotten is that Marciano was truly a great fighter. It was his will to win that made him unbeatable." - Archie Moore
"I had a bad weakness I kept hid throughout my career. I didn't like to be crowded, and Marciano always crowded his opponents. That's why I say I could never have beaten him." - Joe Louis
"He was a great puncher, one of the best of all-time. He just threw one punch after another, and all of them were hard." - Harry "Kid" Mathews