Rocky Marciano stood five feet ten inches in an era when heavyweight champions towered over six feet. He compensated with a work rate and punching power that no opponent could survive for long. He retired with a perfect 49-0 record, the only heavyweight champion in history to leave the sport undefeated.

This episode traces Marciano from his Italian immigrant family in Brockton, Massachusetts through his brutal rise in the heavyweight ranks and his decision to walk away at the peak of his powers.

• He retired with a perfect 49-0 record, the only undefeated heavyweight champion in boxing history
• He stood just five feet ten inches tall and weighed around 185 pounds, small for a heavyweight
• He knocked out Jersey Joe Walcott to win the world heavyweight title in 1952
• He died in a plane crash at forty-five, one day before his forty-sixth birthday