"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.