Former Stanford Cardinal head coach & current San Francisco 49ers head coach Jim Harbaugh once called fullback/linebacker Owen Marecic "the perfect football player". Winner of the inaugural Paul Hornung Award for most versatile college player, Marecic was the bruiser to Stanford's powerful rush attack that nearly unleashed Toby Gerhart to a Heisman Trophy in 2009. He then played both ways in 2010 and helped lock things down for the Cardinal on both sides of the ball, making life easier for Andrew Luck to dominate opposing defenses.
In terms of run blocking, it's hard to get much better than Marecic. Current head coach David Shaw mentioned how he is perhaps the fastest player he's ever coached in anticipating the snap, making him an explosive back who's one step ahead of the rest of his players. What might require some work is his pass catching--fullbacks in the NFL can't just be stuffing it up the middle, they need to show some versatility to give the defense more to think about. Senior Bowl updates have been promising in that regard, as he caught most passes thrown to him today.
Marecic is being targeted by the Philadelphia Eagles according to Bleeding Green Nation, which has to be a nightmare for NFC teams--Philadelphia has had the best rushing attack in the NFL the past two years behind LeSean McCoy, and the last thing they want to deal with is an Andy Reid team that runs as much as it passes. The Minnesota Vikings have also taken a look, potentially to unleash Adrian Peterson, but also reunite him with Gerhart. And don't think Harbaugh and the Niners won't give him some thought either to help out a not so great run attack. There will be options for him if he chooses to turn pro.
Why do we say "chooses"? More on that in a little bit.