When the yellow flag flashed across the screen on Tom Brady's final heave to the end zone, a lot of watchers probably thought pass interference. Brady certainly thought so, and it looks like that should've been the case with a glimpse at the instant replay. Rob Grownkoski was tied up by linebacker Luke Kuechly on the play as Brady threw the interception that clinched the 24-20 win for the Panthers.

But then the referee picked the flag up without explanation, and the play stood. An argument for the play standing was how the ball was underthrown and Gronkowski wasn't going for it. On the other hand, you can argue Gronkowski may have had a chance if he wasn't tied up. Either way the ref didn't provide an explanation and Brady wanted one badly. Badly enough to yell and follow the ref down the field. He came very close to making the same mistake Bill Belichick did last season. Regardless, this is some highly debatable material.

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[via SBNation]