To become one of the greatest running backs in NFL history, you have to be blessed with many physical and mental abilities. Speed, agility, strength, vision, and a host of other critical skills go into building the next Jim Brown, Walter Payton, or Barry Sanders. But even more so than those attributes, there's one thing required of all backs that they simply cannot do without. Something that makes all the difference between a one year wonder and a Hall of Famer: health.

No matter how good a running back you are, if you’re not healthy then you’re simply not going to make your mark on the league in the way you should. Throughout the history of the NFL, guys who could've been all-time greats like Bo Jackson or Terrell Davis had only begun to reach the peak of their powers before a cruel twist of fate cut them down without a moment’s notice. While they do play the position with perhaps the shortest shelf life of any player, it’s nevertheless unfortunate and unexpected when one of the league’s best backs goes down and is never these same. Here we present A History of NFL Running Back Careers Ruined by Injury.

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