Abstract: An electronically actuated first down marking system and associated method includes first and second marking assemblies positioned on a first sideline of a playing field, and third and fourth marking assemblies positioned on a second sideline of the playing field and opposite of the first and second marking assemblies. A mechanism determines a distance between the first and second marking assemblies, and a mechanism aligns the first and second marking assemblies with the third and fourth marking assemblies. The aligning mechanism and the distance determining mechanism are independently and simultaneously operable during game conditions. A mechanism determines whether a mobile game ball has penetrated a first down plane defined by the second and fourth identification marking assemblies.