Jarret Stoll scored 4:27 into overtime to give the Los Angeles Kings a 2-1 victory and eliminate the Vancouver Canucks 4-1 in their first-round matchup.
It is the 10th time a No. 8 seed has knocked out a No. 1 seed since the NHL went to a conference playoff alignment in 1994.
Henrik Sedin gave Vancouver the lead with his second goal of the series in the first period and the Canucks held that edge until early in the third period when Brad Richardson tied it.
Jonathan Quick made 26 saves, Cory Schneider made 35 saves and Roberto Luongo sat on the bench and watched for the second straight game.
The winner of the Blackhawks-Coyotes series will meet the Nashville Predators in the second round, with the Kings squaring off against the St. Louis Blues.
Watch the highlights from the overtime thriller here: