Saquon Barkley, who is perhaps the most hyped running back prospect since Reggie Bush, arrives at an interesting point in NFL history. The running back is no longer a "premier" position in the draft -- NFL teams would much rather use a high pick on a quarterback, offensive tackle, pass-rusher, or wide receiver.

Proponents of advanced statistics have been at the forefront of this change of thinking, pointing out that running backs often have short careers and are usually replaced with ease.

Accordingly, any team willing to go against this trend and use a high pick on Barkley should be fairly certain that he is likely to live up to his hype. Enter BackCAST, which is Football Outsiders' metric for projecting the likelihood of success for running back prospects in the NFL draft.

Historically, a college running back with a good size-speed combination, a high average yards per carry, and who represented a large percentage of his college team's running attack is more likely to succeed at the NFL level. BackCAST considers these factors and projects the degree to which the running back will exceed the NFL production of an "average" drafted running back during his first five years in the NFL. For example, a running back with a plus-50 percent BackCAST is projected to gain 50 percent more yards than the "average" drafted running back. BackCAST also projects whether each running back is likely to be heavily involved in the receiving game or is more of a "ground-and-pound" back.

We have run BackCAST for all of this year's top prospects, and there is a huge gap between No. 1 and the rest of the group. This draft is also a weak one for receiving running backs -- with one notable exception.