Rocky Marciano ( born Rocco Francis Marchegiano ; September 1 , 1923 - August 31 , 1969 ) was an American professional boxer and the World Heavyweight Champion from September 23 , 1952 , to April 27 , 1956 .
Rocco Francis Marchegiano , better known as Rocky Marciano ( September 1 , 1923 - August 31 , 1969 ) , was an American boxer .