Melker Karlsson scored at 3:22 of overtime and the San Jose Sharks came back to beat the Edmonton Oilers 3-2 on Wednesday night in Game 1 of their Western Conference series.
The Oilers jumped out to a 2-0 first-period lead only for the veteran Sharks to come back and tie the game with just over 15 minutes to play.
Milan Lucic and Oscar Klefbom scored for the Oilers.
Joel Ward and Paul Martin scored for San Jose.
Edmonton center Connor McDavid, the NHL's leading scorer in the regular season, had one assist in his playoff debut to extend his points streak to 15 games.
It was the first playoff game in the Oilers' new downtown arena and the team's first NHL postseason game in almost 11 years.
The Sharks played without star center Joe Thornton, who is day-to-day with a left knee injury.
However, San Jose center Logan Couture returned to the lineup, with a full-face cage. He missed seven games after having his mouth and teeth smashed by a deflected puck.
Klefbom scored the Oilers' first playoff goal since 2006 when he took a cross-ice pass in the high slot from Jordan Eberle and fired the puck low between the pads of Sharks goalie Martin Jones at 6:44.
Lucic made it 2-0 with less than three minutes to go in the period on the power play.
McDavid passed the puck to Mark Letestu, who rifled the puck off Jones' goal pad right to Lucic. Lucic then shot again through Jones's pads.
The Sharks rebounded, dominating play for long stretches in the second and third periods. The teams each had 10 shots in the first period, but San Jose outshot Edmonton 28-7 through the next 40 minutes.
San Jose cut the lead in half 1:43 into the second period on the power play. Winger Joonas Donskoi came around behind the net and fed the puck in front on the backhand to Ward, who then redirected the puck past Oilers goalie Cam Talbot.
San Jose tied the game just over five minutes into the third period when Martin jumped on a rebound off Tomas Hertl's wraparound shot and put the puck in.
The Sharks' power play, ranked 25th in the regular season at 16.7 percent, was otherwise ineffective. San Jose was 1 for 6 with the man advantage while Edmonton was 1 for 3.
Game 2 is Friday in Edmonton.