The Edmonton Oilers and Colorado Avalanche are headed to overtime in Game 4 of the Western Conference Final.

It looked like the Avalanche were on their way to a sweep when Zack Kassian scored the equalizing goal with just over four minutes remaining in regulation to send the game to overtime and momentarily avoid a sweep.

The Oilers held a two-goal lead until midway through the third period when Gabriel Landeskog, Nathan MacKinnon, and Mikko Rantanen scored in a six minute span to give the Avs a one-goal lead at 14:47 of the period.

Edmonton held a 3-1 lead entering the third but Devon Toews cut into the lead 31 seconds into the period, firing a shot from the point past a screened Mike Smith for his fifth of the postseason.

Zach Hyman brought he lead back to two, sending a fluttering one-timer past Pavel Francouz for his second of the game and ninth tally in his past nine games.