Field Judge
The Field Judge stands on on the same (home) sideline as the line judge, but 20 yards deep instead of along the line of scrimmage.
The Field Judge must count all defensive players at the time of the snap, to make sure there aren't too many. The Field Judge is also responsible for watching all of the eligible receivers on their side of the field, making complete/incomplete rulings,
calling downfield penalties (such as pass interference or illegal man downfield) and spotting the ball in-bounds or out-of-bounds.
The Field Judge also works with the Back Judge to signal if field goals are good or no good.
Side Judge
The Side Judge
has the same responsibilities as the Field Judge, just on the visitor's side of the field.
You can't go to, watch, listen to or even talk about an NFL game without "the refs" getting brought up. "The refs" are an integral part of the game...
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