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Alabama running back Trent Richardson is widely considered a top 15 pick in NFL draft, but he is not going in the first round. Running backs have been devalued in the NFL draft and Richardson's lack of off-the-charts athleticism is going to cost him.

Declining Value of RBs

NFL teams have become more and more reluctant to draft running backs in the first round. It is now one of the most lightly drafted positions in the opening round.

Over the last two years only four RBs have been taken in the first round.

In 2010 three RBs went in the first: No. 9 CJ Spiller No. 12 Ryan Mathews No. 30 Jahvid Best. None of these players showed they were worthy of their lofty selection in their rookie seasons, and the RB draft value fell even further.

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Last year, Mark Ingram was the first ball carrier off the board at No. 28. Ingram had the terrific resume and solid athleticism to go higher, but he almost slid out of the first because teams would rather take RBs in the later rounds.

Why Trent Richardson Will Fall

Like Ingram, Richardson has a great resume and history of success. Check out some of his highlights.

What he lacks, though, is stellar athleticism. Richardson will probably only work out at his pro day, and when he does he will display less than elite lateral quickness and a 40 time between 4.5 and 4.7.

You combine those results with the reluctance to draft RBs high in the first, and you get Richardson lasting until the second.

Will Any RBs go in the 1st?

Yes, one will. I predict Cincinnati will spend one of their two first-round picks on Miami RB Lamar Miller.

The fact that I have Miller going before Richardson is sure to raise some eyebrows, but Miller has more explosion and versatility.

The Bengals will want to add a big play threat at running back to go with skill position young guns Andy Dalton and AJ Green. Miller will be that guy—assuming he enters the draft.

Check out some of Miller's highlights, and see my full first round mock draft below.

Here is my full first-round mock: