Ah - no I see what you're asking .... Yes, they have to make an educated guess as to where the ball is, but then again, we are only talking about inches here. There are three feet between every yard
The ball is placed on the 35 yard line of the opposing side's end of the field. There are 3 sticks used for marking ball position on the sideline. You have the "chains" as well as a ball position stick

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