Marian Gaborik tallied with 5:19 remaining in the third overtime, sending the New York Rangers past Washington, 2-1, in Game 3 of this Eastern Conference semifinal from Verizon Center.
Rangers center Brad Richards gained control of the puck off a Dan Girardi wraparound to the left rear of the Washington net, and fed in front for Gaborik, who ripped a wrister home to cap the marathon contest.
The score prevented the Blueshirts from sharing a slice of dubious NHL history. New York had dropped seven straight OT playoff games, one off the league mark held by both the Flyers and Flames.
Ryan Callahan netted a second-period power-play goal for the Rangers, who snagged a 2-1 series edge.
Henrik Lundqvist stopped 45 shots, while his counterpart Braden Holtby made 47 saves.
"I hope it gets Gabby (Gaborik) going, it's a guy we need as we continue," Rangers head coach John Tortorella said of Gaborik's game-winner.
John Carlson picked up the regulation score for the Capitals, who have two days off to regroup before hosting Game 4 on Saturday afternoon.
"You go into triple overtime, it's a special game, but it's just one game and you have to bounce back," Capitals head coach Dale Hunter said.
The visitors snapped the scoreless deadlock at 6:41 of the second period on a power play. Michael Del Zotto's left-point drive pinballed off several players on the way to Holtby, and Callahan was in the right place to swat home the rebound from atop the crease.
Carlson equalized for the hosts at 11:10, thanks to a no-look shot into the upper-left corner, but Lundqvist came up big on Brooks Laich, foiling a 3-on-1 rush during a subsequent Washington power play.
Troy Brouwer's redirection off a Matt Hendricks dish narrowly missed the net wide right five minutes into the first extra session, and Alex Ovechkin caused a turnover in the left circle with five minutes to go, but his shot rolled and hit the right post.
Alexander Semin was called for tripping Callahan with 2:28 remaining in the first OT, but the Caps played well shorthanded.
Michael Rupp then had a chance from the right side with almost 6 1/2 minutes gone in the second overtime, but the shot hit teammate Brian Boyle instead.
The hosts survived a high-sticking call to Mike Green early in the sixth period.
Gaborik hit the right post as the clock ticked down to eight minutes to play in the final stanza, then Dennis Wideman rang one off the opposite post just over a minute before the winner was scored.
Prior to Wednesday, the Rangers' last overtime win in the postseason occurred on April 29, 2007, a 2-1 double-OT decision against Buffalo in Game 3 of the Eastern semis...The Flyers' stretch of overtime frustration lasted from April 18, 1996 until April 18, 2000, while the Flames came up short from April 16, 1991 through April 17, 2004...Washington's last triple-OT playoff tilt happened on April 20, 2003, a 2-1 loss to Tampa Bay in Game 4 of an Eastern quarterfinal...New York's last six-period postseason tilt was a 3-2 win over Chicago in Game 6 of the semifinals on April 29, 1971...The Capitals had won their previous five playoff overtime games against the Rangers, dating back to April 23, 1986 -- Game 4 of the Patrick Division finals.