Running back

A running back (RB) is the position of a player on an American football team. They are the players who carry the ball the most. They receive handoffs, catch passes, and block for other runners.

 References 
 Football 101: Basic Football positions 
 http://www.dummies.com/how-to/content/what-the-running-backs-do-in-a-football-game.html 

Category:American football positions