Looking just at the stats, O.J. seems to have the weakest season among the 2,000-yard club. He was last in rushing yards, receiving yards and total touchdowns. So why is he number one?
Because O.J. Simpson rushed for his 2,000 in only 14 games, the length of the season in 1973. No one has ever made it to 2,000 yards in 14 games except O.J. The next best was Eric Dickerson getting to 2,000 in 15 games.
To get to 2,000 yards in 14 games, O.J. had to average 143.1 yards a game, which is the all-time record. The second best to that is Jim Brown's 133.1 yards per game—10 yards less.
O.J. dominated on the ground that season like no one ever had before, and probably ever will again. If O.J. had played 16 games like everyone else in the 2,000-yard club and kept up his pace, he would have had 2,289 yards—184 more yards than Dickerson.
So even though he has the least yards, O.J. Simpson gets number one because he had the best season rushing ever.