The NHL made its return to the ice Saturday after a 142-day hiatus.
Five qualifying round contests began in the hub cities of Toronto and Edmonton.
The Oilers find themselves down against the Blackhawks despite home ice advantage falling 6-4 in the opener of their best-of-five series.
Elsewhere, Jeff Petry scored the winner in overtime as the Canadiens beat the Penguins 3-2 in game one.
And in the late game, the Flames beat the Jets 4-1 to open their series.
The Maple Leafs get back on the ice Sunday night against Columbus.
Puck drops at 8pm.