It wasn't so long ago that running back was perceived to be one of the deepest and strongest units for the 2014 Trojans.

And while that may still be the case this year, there are potential problems looming on the horizon in 2015 and perhaps beyond.

The trouble started when the school announced that sophomore running back Ty Isaac would be transferring closer to his Illinois home.

Though he is a very good back, in and of itself, USC could absorb his loss in a typical year when a focus could be made on replenishing the unit through this year's recruiting class.

However, as Bleacher Report - College Football
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