9. Buffalo Bills vs. Chicago Bears (2014)
Buffalo wasn’t great through much of the last decade. But they pulled off an overtime upset over the Bears in 2014. Fred Jackson was the oldest running back in the NFL but nobody would have guessed it. That’s because his 38-yard run helped to set up Dan Carpenter’s winning field goal. The Bears were favorites on opening day but Buffalo didn’t pander to expectations. They were relentless against a technically better team.

The final score at Soldier Field was 23-20. But this one stung the Bears because they should have had the game wrapped up. Buffalo led the game before Chicago fought back. They won the coin toss to start overtime. However, the Bills forced turnovers and played with a never-say-die attitude. They were sizable underdogs but proved that anybody in the NFL can win (via Democrat & Chronicle).