The Chicago Film Archives put up a short YouTube clip of the Chicago Blackhawks playing against characters from Sesame Street in 1970. There is no sound, but who needs it when the sight of Big Bird threatening a player is good enough?
There's no explanation for this, but according to The AV Club, this might have been for a commercial or promotional video.
In any case, you should never, ever mess with a Muppet.
Seriously, jump to 7:25 and watch Big Bird tower over a Blackhawks player again:
(via The AV Club)