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A play in doubles tennis in which the net player of the serving team stands at the center of the court, signalling behind his back which way he is going when the server serves. Done to confuse opponents, often used by the Bryan Brothers.
Returner1: SHIT!!! Which way is the net player going?
Returner2: I don't know, they are running an I Formation Monster.
by TennisJohn August 20, 2006
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