While it is true that Eric Dickerson holds the single season *total* rushing yards record, he accomplished this in a 16-game season. On the other hand, O.J. Simpson is the only player in NFL history to break the 2,000 yard barrier in a single 14-game season. O.J. Simpson gained 143 yards per game in his record-breaking season, while Dickerson only gained 131 yards per game in his. So, the answer depends on whether you are interested in total yards or yards per game.
Who holds the single season rushing yards in NFL?