PITTSBURGH -- Evgeny Kuznetsov scored at 5:27 of overtime, and the Washington Capitals advanced to the Eastern Conference Final with a 2-1 win against the Pittsburgh Penguins in Game 6 of the second round at PPG Paints Arena on Monday.
Alex Ovechkin passed to Kuznetsov, who split the defense before beating goaltender Matt Murray five-hole on a breakaway. Kuznetsov had four points (two goals, two assists) in the past two games.
[WATCH: All Capitals vs. Penguins highlights | Complete Capitals vs. Penguins series coverage]
"I see [Kuznetsov] was over there and I just put the puck in space and he did what he does best," Ovechkin said. "It feels great. Never been this position before and I'm looking forward to [the conference final]."
The Capitals, who lost to the Penguins in the second round in each of the previous two Stanley Cup Playoffs, will play the Tampa Bay Lightning in their first conference final since 1998.
Video: #ThirstForTheCup: Caps heading to Conference Final
"We believe in each other," Ovechkin said. "It doesn't matter what happened [in the past]. We have to stick together. We knew it was there. We just had to battle, and we just had to fight through it. Again, great feeling right now and we're going forward."
Alex Chiasson scored, and Braden Holtby made 21 saves for Washington.
Kris Letang scored, and Murray made 28 saves for Pittsburgh, which was the two-time defending Stanley Cup champion and lost for the first time in five games when facing elimination since hiring coach Mike Sullivan on Dec. 12, 2015.
"I think sometimes we all learn more from our failures than we do our successes," Sullivan said. "I think this group knows how hard it is to win in the playoffs. All the teams are really good. There's a fine line between winning and losing. We haven't tasted this in a long time, and that's a credit to the group of players that is in that dressing room."
Chiasson gave the Capitals a 1-0 lead at 2:13 of the second period. Nathan Walker skated the puck behind the net before passing to Chiasson, who beat Murray short side on a one-timer from the right circle. The goal was Chiasson's first point in the playoffs (12 games) and first since 2014 when he played for the Dallas Stars.
Video: WSH@PIT, Gm6: Chiasson buries opening goal
With the assist, Walker became the first Australian to get a point in the playoffs.
Jakub Vrana had an opportunity to extend the lead to 2-0 on a partial breakaway at 6:17, but Murray made a blocker save on his wrist shot.
Letang tied it 1-1 with a slap shot from the point that deflected off Chandler Stephenson's stick and past Holtby's blocker at 11:52 of the second.
Sidney Crosby had a chance to give the Penguins the lead when he deflected a pass from Bryan Rust on goal 17:26 of the third period. Holtby made the save on Crosby's initial shot and Patric Hornqvist missed on the rebound.
"It's hard to get there, regardless of winning two years prior," Crosby said. "I know everyone talked about [winning a third straight championship], but just getting in there and how hard it is, especially with the group we have, a lot of the same guys that have been together for a couple of them, that's what you play for. It's the best time of year. Unfortunately, we couldn't get it done."
Goal of the game
Kuznetsov's goal at 5:27 of overtime.
Video: WSH@PIT, Gm6: Kuznetsov ends series with OT winner
Save of the game
Holtby's save on Justin Schultz with seven seconds left in the second period.
Video: WSH@PIT, Gm6: Holtby denies Schultz late in the 2nd
Highlight of the game
Letang's goal at 11:52 of the second period.
Video: WSH@PIT, Gm6: Letang pots one-timer through traffic
They said it
"This group has been resilient. … The great thing about this is all day I knew we were going to win. I don't know why, but this group has a lot of resiliency. And first of all, there are some great champions in that other room, great players. What they've done and accomplished the last couple years is pretty remarkable. This is a tough league." -- Capitals coach Barry Trotz
"They were just the better team. I thought they played a heck of a game tonight. It didn't feel like we really had many chances at all. They're a great team and they showed it. They deserved to win tonight." -- Penguins goalie Matt Murray
Need to know
Capitals forward Nicklas Backstrom did not play with an upper-body injury he sustained in the third period of Game 5. Lars Eller replaced him on the second line. Backstrom is day to day. … Capitals forward Travis Boyd had one shot and two blocks in 12:12 of ice time in his NHL playoff debut. … Crosby, who had an assist on Letang's goal, has 185 playoff points (66 goals, 119 assists), tying Steve Yzerman for 10th all-time. … Washington won a playoff series against Pittsburgh for the first time since the 1994 Eastern Conference Quarterfinals (2-9).
Video: Dunkin Donuts Breakaways: Kuznetsov's series-clincher
Capitals: Game 1 of Eastern Conference Final at Tampa Bay (8 p.m. ET; NBCSN, TVAS)
Penguins: Season over
Video: Kuznetsov scores in OT, Caps advance to ECF
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