Matt Duchene's Offside Goal
You know a referees' decision is a bad one when even the team that benefits from it seems hesitant. Watch Matt Duchene almost come to a halt after receiving a pass that clearly put him offside.
As you can see, despite the obvious offside, the linesman was oblivious and the goal counted. To make matters worse, the Avalanche beat the Predators by one goal, 6-5.