 Second , Schulz is credited with being the first center to step back from the line while playing defense . Prior to Schulz 's innovation , centers played in the line on defense . In 1905 , Schulz began dropping back from the line , enabling him to use his speed to move laterally and giving him greater coverage across the field of play . At the time , the innovation was referred to as a " roving center " , but it was effectively the birth of the linebacker position in American football . Asked how he developed the " roving center " idea , Schulz noted that the backs started from five yards behind the line and concluded , " No back living could move five yards while I was moving four " . He described his thinking to Coach Yost this way : " It 's all very simple , Yost . The ball carrier travels five yards while I travel only four yard to meet him . I know of no back who can beat me in a five @-@ yard race after giving me a one @-@ yard handicap " . 
