Only six players in NFL history have ever rushed for 2,000 or more yards in one season, with Tennessee's Chris Johnson joining the exclusive club in 2009.
Only once did it happen in back-to-back seasons: Barry Sanders in 1997 and Terrell Davis in 1998. Might anyone accomplish the feat in 2010? Maybe it will be an uncapped year on the field, too.
In the meantime, have a look at the NFL's 2,000-yard club.