But they shut out the New York Rangers the rest of the night. They got a goal from Joel Ward to tie the game. They kept peppering Henrik Lundqvist, who denied league MVP candidate Alex Ovechkin nine times.
Then, at 9:24 of overtime, Mike Ribeiro scored his first playoff goal in five years. The Capitals had a 2-1 win over the Rangers. Series lead restored. Momentum regained. Doubts erased — for at least another couple of days.
"Obviously just kind of got the nerves out there at the start," said Ward, who scored in the second period, "and fed off the crowd for the game. You know, we executed a couple times, got some chances and so did they, but we were fortunate to bury the last one."
The Capitals now take their 3-2 series lead to New York for Sunday's Game 6. The home team has won every game so far, with Washington taking the first two and New York pulling even in Games 3 and 4.
Washington has also been fighting history along the way: The franchise has lost eight playoff series in which it has held a two-game lead, leading to collective jitters any time the other team mounts a comeback.
Now it's the Rangers who face a must-win in a series in which four of five games have been decided by one goal.
"It's just a bounce here and there," said Lundqvist, who finished with 33 saves. "It's been that way the whole series. We have to continue to be positive and believe that we can do it."
Ribeiro hadn't scored in the post-season since 2008, when he was playing with the Dallas Stars. He had never scored a winning goal in the playoffs until he opportunistically found the puck on his stick near the crease after a pinball deflection of a shot from Karl Alzner at the point.
"I know I was behind that D, and the puck just came onto my stick," Ribeiro said. "It was pretty cool."
Brian Boyle scored the Rangers' lone goal 53 seconds into the game, but he also took a needless penalty that set up Ward's power play goal in the second period. Braden Holtby (24 saves) and Lundqvist matched each other for the rest of regulation — and a little beyond.
Still, the Capitals were tight early on. Coach Adam Oates said before the game he was "worried" about the way his team would start out. His concern was justified.
Dan Girardi dumped the puck behind the net. Derick Brassard was there and made a one-touch pass to Boyle, who had skated in front of the crease with barely a hindrance from Capitals defencemen. Boyle popped in his second goal of the series, and Brassard had his series-leading fifth assist.
The Capitals stayed out of sorts well into the first period. Jason Chimera (boarding) and John Erskine (elbowing) took penalties. New York nearly took a two-goal lead when Erskine turned the puck over at centre ice, but he recovered in time to stop Carl Hagelin's breakaway.
The Rangers finally gave away the momentum when Boyle slashed Ribeiro for no good reason in front of a referee near the Rangers' net. It took only 11 seconds for the Capitals' power play, the NHL's best during the regular season, to tie the score on Ward's one-timer from the slot.
"It's a dumb penalty, and you don't kill those off," Rangers coach John Tortorella said. "It just happens that way in our game. That's a guy that's playing really well for us, but that's a dumb penalty."
The Capitals survived two more Rangers power plays late in the second period, then came up empty with a chance of their own early in the third — all because of Lundqvist. The goalie stopped Ovechkin three times from point-blank range during the man advantage, the last two without a stick.
Lundqvist stopped Ovechkin three more times in overtime, but there was no stopping Ribeiro when the game's final loose puck fell the Capitals' way.
"It was just a quick play. Not really much you can do about it," Lundqvist said. "I just wish we got a better bounce. Frustrating and disappointing, but it's not over. We have to regroup."
Notes: New York LW Ryane Clowe, who drew the boarding call on Chimera, played only one more shift after the penalty. He was playing in his second game since missing four with a suspected concussion. ... Rangers D Marc Staal remained sidelined with an eye injury. He has played in only one game in the series. ... With RW Martin Erat out with an upper-body injury, 19-year-old F Tom Wilson, a 2012 first-round draft pick, made his Capitals debut.
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