Rocco Francis Marchegiano, better known as Rocky Marciano, was an American professional boxer who competed from 1947 to 1955. He held the world heavyweight championship from 1952 to 1956, and remains the only heavyweight champion to finish his career undefeated. His six title defenses were against Jersey Joe Walcott (from whom he had taken the title), Roland La Starza, Ezzard Charles (twice), Don Cockell and Archie Moore.
Known for his relentless fighting style, formidable punching power, stamina, and exceptionally durable chin, Marciano is considered one of the greatest heavyweight boxers of all time. Marciano remains the only fighter to have stopped every opponent he ever faced for the world heavyweight title, and holds the highest knockout-to-win percentage in world heavyweight title fights at 85.71%. His career knockout-to-win percentage of 87.8% remains one of the highest in heavyweight boxing history. Marciano is ranked #14 in The Ring magazine's list of the 100 greatest punchers of all time.