1. Walter Payton- Probably the 3rd most powerful back of all time. Top 5 elusiveness of all time. And actually faster than you think. Arguably the best receiving back of all time considering his era. Arguably the best blocking back of all time. Arguably the best goal line/short yardage back of all time. He could even pass. What couldn't he do? Oh, and did I mention he ran behind an even worse line than Barry Sanders.
2. Jim Brown- Really ahead of his time. The most dominant runner ever, but only played 9 seasons and the NFL didn't really become legit until the 70s. I just can't put him ahead of Payton.
3. O.J. Simpson- Only had a handful of solid years, but they were all great. Probably had the best prime of any runner ever. His 1973 season with 2000 yards in 14 games behind a poor offensive line is still the gold standard for runners.
4. Barry Sanders- The most electric runner ever. But he came out on short yardage and ran for the most negative yards in history. Still with a career 5.0 ypc his greatness is unquestioned.
5. Eric Dickerson- Still holds the single season rushing record. But this is where the drop off starts. The top 4 IMO are clearly the immortals of pro running backs. Dickerson was unquestionably a dominant runner and tough as nails to handle his extreme workload.
6. LDT- An exceptionally well rounded back. While he doesn't have the pure running skills of just about all on this list, he could do everything well. He was a modern day Walter Payton, but quite frankly just not as good.
7. Emmitt Smith- Without a doubt this man got the most bang for his buck. Yes he wasn't all that fast. Yes he wasn't all that strong. Yes he wasn't all elusive. And yes his career ypc is only 4.2, but guess what? This man is still the all time leading rusher. It DOES mean something.
8. Earl Campbell- Exceptionally powerful, but overrated. He only really lasted 3 seasons. And they weren't as dominant as the primes of Brown and Simpson, but he was still the most destructive man in NFL history. Not much lateral agility. Speed wasn't all that great. Couldn't catch, but my god he could run over you.
9. Marshall Faulk- This guy was a weapon. He didn't really have much of a carry workload and his single season career high in rushing yards is only 1359. But he was devastating in the passing game. He was the engine to the Greatest Show on Turf.
10. Adrian Peterson- I didn't just conveniently put him at #10 to round off the list. I truly believe he is number 10. This last year gave him an element of dominance that most great runners have. His 2008 campaign was real solid and some guys on this list would kill to have that season. But this last year really separated him and you have to say as far as pure rushing he's up there with Payton, Brown, Simpson and Sanders. Time will tell if he can climb the list.
Honorable Mention- Tony Dorsett.