Carolina didn't require another RB - they have three. But they're all big backs. Finally, Ron Rivera got his Darren Sproles type player.
RB and returner, and sometimes receiver. Barner was a feature player in one of the best college offenses around. The 5'9, 200 lb speedster looks to be best as a complimentary player, with a good change of direction and home run ability.
It's a bizarre pick at first, but it's the ability to add to the offense in the 6th. That's rare this late in the draft. Not all of the current RB will be here in 2014, you have to assume, and at that point, a guy like this could be a lot more valuable.