BATTERSEYE
Batter's eye
The batter's eye or batter's eye screen is a solid-colored, usually dark area beyond the center field wall of a baseball stadium, that is the visual backdrop directly in the line of sight of a baseball batter, while facing the pitcher and awaiting a pitch. This dark surface allows the batter to see the pitched ball against a sharply contrasted and uncluttered background. Its primary purpose is the safety of the batter. The use of a batter's background has been standard in baseball since at least the late 19th century. The batter's eye performs the same role at a baseball venue as the sightscreen does at a cricket venue, except ...The above text is a snippet from Wikipedia: Batter's eye
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