Curtis Lazar scored in triple overtime for the Edmonton Oil Kings in a 4-3 win over the Val-d'Or Foreurs in Friday's Memorial Cup semifinal.
The Oil Kings will meet the unbeaten Guelph Storm in Sunday's championship game.
Lazar deflected a Cody Corbett shot from the blue-line by Val-d'Or goalie Antoine Bibeau after 102 minutes 42 seconds of play, which made it the longest game in Memorial Cup history.
The previous record was 95 minutes 41 seconds set in London in 2005 when the Ottawa 67's beat the Kelowna Rockets in double overtime.
Mads Eller, Mitch Moroz and Edgars Kulda also scored for Edmonton, while goalie Tristan Jarry stopped 46 shots for the Western Hockey League champions.
Val-d'Or defenceman Guillaume Gelinas scored with 36 seconds remaining in regulation to send the game into overtime. Phil Pietroniro and Randy Gazzola also scored for the Foreurs. Bibeau made 50 saves in the loss.
This is Edmonton's second trip to the Memorial Cup in three years, but will play in their first final since 1971. The Oil Kings lost the tiebreaker game two years ago to host Shawinigan.
Val-d'Or's elimination from contention snaps a three-year run of QMJHL teams winning the Cup. The OHL's Windsor Spitfires took it in 2009 and 2010.
Edmonton is a win away from becoming the first WHL team to win it since the Spokane Chiefs in 2008. Spokane's goaltender that year was Dustin Tokarski, who is currently tending the Montreal Canadiens' net in the NHL's Eastern Conference final.
The Oil Kings opened with a 5-2 loss to the Storm before beating the host London Knights by the same score.
Edmonton lost 4-3 in double overtime to Val-d'Or in the round-robin Tuesday, despite leading 2-0 after the first period and 3-2 with less than five minutes to go in the third. That game ended after 81 minutes 15 seconds.
Guelph did Edmonton a favour by eliminating the Knights from contention, which kept the Oil Kings from playing a tiebreaker game Thursday against London.
Gelinas was back in Val-d'Or's lineup Friday after suffering a leg contusion Monday in a knee-on-knee collision with Guelph's Chadd Bauman. Gelinas sat out the round-robin game against Edmonton the following night.
The QMJHL's top-scoring defencemen played regular shifts and threw a hip check on Edmonton's Riley Kieser despite looking uncomfortable at times.
But with Bibeau pulled for an extra attacker, Gelinas threaded a shot from the blue-line through traffic that forced a second overtime game between these two teams in the tournament.
With Oil Kings defenceman Ashton Sautner serving a delay-of-game minor in the second overtime, the Foreurs had a chance to end it , but Jarry stopped Nicolas Aube-Kubel on a breakaway.
The Foreurs drew within a goal at 17:82 of the second period when Gazzola beat Jarry between the pads with an off-speed shot
Val-d'Or turned the puck over inside the blue-line with Reid Petryk dishing to Kulda to make it 3-1 at 9:45. The Latvian froze Bibeau with a quick deke and a backhand.
The Oil Kings pulled ahead on Moroz's power-play goal at 6:34 when the Edmonton Oilers prospect beat Bibeau with a low wrist shot from the high slot.
With an extra attacker on the ice for a delayed penalty, Eller backhanded a rebound by Bibeau nine minutes into the game.
Pietroniro scored at 1:49 on a wrist shot that beat Jarry glove side. A few minutes later, the defenceman took a hit in Val-d'Or zone. He skated off holding his shoulder and didn't return to the game.