I vote the Shea injury to Erin, not because of another player for a rival team, but for different reasons:
a.) the guy went from doing jack shit and never getting to the QB to finally get there. In the process, injuring a prolific quarterback.
b.) the game went from looking like a miserable run-of-the-mill Pack thrashing of the Bears to the battle of the backup QB's.
c.) Rodgers was acting like a douche up until his injury. Pushing cameras aside, mean mugging security workers, and just being a dick. Next thing you know, he's on the sidelines looking like he could either cry or kill someone.
d.) I think winning that game woke the Bears fans up (kind of) for the rest of the season. After our favorite team wound up beating a division rival in their own house, it actually gave me some false hope for a while that the Bears could make it to the post-season.
So there's my vote. or maybe it should just be "Bears win in Lameblow". Your call.