Santa Monica College Football Lineman's Eric Acosta, 19, (left) an  offense  center, charges into defensive gaurd  Idin Azadipour, 18, during spring practice at SMC's Corsair Field  on Wednesday, May 16, 2007. Lineman is a position in American football that are the frontline players of the offense or defense of any play during the game. The linemen are usually the largest players on the team, with professional players weighing over 300 pounds.