The Lightning moved three points ahead of the Boston Bruins for first place in the Atlantic Division. Nikita Kucherov extended his point streak to seven games (five goals, seven assists).
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"[The standings] are close," Point said. "We look at it, but definitely more focused on what we're doing down the stretch, hopefully, heading into playoffs."
Alex Ovechkin scored his League-leading 36th goal to cut the lead to 3-2 at 11:02 of the third period and is six away from 600 in his NHL career. But Kucherov scored his 32nd goal at 12:58 to make it 4-2.
"It's definitely a huge win for us, especially against a team that's playing well," Kucherov said. "It's always tough to play well in their building. I don't think we had a lot of success in the past few years here. It's just a good start of a road trip."
Braden Holtby made 15 saves and Lars Eller scored a power-play goal for the Capitals (34-19-7), who are one point ahead of the Pittsburgh Penguins for first place in the Metropolitan Division.
"I think we lose the game in the first period today," Eller said. "Three is a lot to catch up, especially when you're playing the No. 1 team in the League. Was it doable? Yeah. We were close, but it'd be a lot easier if we weren't down three."