Sigmund Bloom's 2012 NFL Draft Stock Watch: Stock Up/Down on Top RB Prospects

The running back board has been set in motion by the combine and it will continue to shift as pro day results come in. An early look at who is on the move.

UP

Robert Turbin, Utah State: Turbin was a chiseled 5'10", 222 lbs. and he showed he was completely over a 2010 ACL tear with a 4.5 40-yard dash and a 36-inch vertical leap. He'll probably fall to the third day in this deep class, but he has starter potential.

Isaiah Pead, Cincinnati: The Bengals showed up for this hometown back's pro day, and he continued to win over teams with his strong all-around game and special teams value after a strong Senior Bowl and combine.

Doug Martin, Boise State: Martin has leapfrogged all of the backs at the Pac-10 schools that didn't recruit him with a very strong Senior Bowl week and combine performance, comparing favorably to 2008 No. 13 overall pick Jonathan Stewart.

DOWN

Lennon Creer, Louisiana Tech: Creer ducked competition at Tennessee when he was stuck behind Montario Hardesty and saw that uber-prospect Bryce Brown was coming to Knoxville. But he couldn't avoid coming in at the tail end of the combine competition with a 4.71 40 and poor performance in drills.

Darrell Scott, South Florida: Once the most vied-after running back recruits in the nation, Scott lumbered to a 4.73 40 and probably assured that he will not be drafted.

Vick Ballard, Mississippi State: Ballard's combine will be remembered for his comical fall during his 40, but otherwise his combine numbers painted the picture of a marginal NFL back.

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