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Rob Gronkowski is a coverage nightmare for the majority of the NFL. Opposing teams know they need to cover the New England Patriots tight end, but that's easier said than done.

So how does Gronk get so wide open? Well, Real Football Network's Pat Kirwan believes it has a lot to do with the triple surface formations New England runs, which free Gronkowski up against zone defense.

Check out Kirwan's explanation in the video above.

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Thumbnail photo via Matthew Emmons/USA TODAY Sports Images