Not sure any of these are the worst....I kind of lean to that Colorado 5th down (just because it was such a collective failure). From an ND perspective, I would say the MSU Little Giants sticks out the most, again(as stated by others because it seemed there were several different fouls. Have heard about the mystery calls at USC during Ara's first year, but never seen video, so hard for me to say.
There are some bad ones in here; not sure the first two seem quite as 'off'. #4 is REALLY bad, and #5 and #6 are terrible too....
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This one was bad from a few years ago....even reviewed, and the replay official watched it from a ridiculously stupid angle. Seriously, from behind the kicker you can clearly see the ball pass in front of the uprights....how much more indisputable do you need?
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Another call that involved ND: still scratch my head about the 'Roughing the Snapper' call in the game against Washington in 2009.