At the start of this decade, a handful of elite NFL quarterbacks began to get very good at something called the back-shoulder throw.

When done properly, this pass drops in behind a speeding receiver's outside shoulder, the one furthest from a pursuing defender. It doesn't matter if the receiver is covered; this pass makes him open, since it takes advantage of the defender's momentum. Throw it to a sure-handed player with long arms and it is nearly impossible to stop.

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