11. Rocky Marciano and Joe Walcott
Fight: Rocky Marciano vs. Joe Walcott
You know how older folks say boxers back in the day got into these epic slugfests that left both fighters' faces battered and bruised beyond recognition. Now we believe them. In a classic battle for the heavyweight title, Marciano and Jersey Joe went at it for 13 rounds before Rocky knocked him out. See, back in the day, the top two fighters in the game used to, you know, have balls to fight each other! Hear that Money May?