After missing two games with a shoulder injury, Alex Ovechkin scores two goals against the Islanders. (Jonathan Newton/The Washington Post)

The list of things that went right for the Washington Capitals on Tuesday night is long and noteworthy. Alex Ovechkin returned from a two-game absence to score twice and add an assist. Marcus Johansson, occasionally frustrated, scored his first goal. The relentless power play scored four times in six chances, and the night ended with Ovechkin smearing a shaving cream pie across the face of rookie Tom Wilson, a baptism in honor of Wilson’s first NHL goal.

“I thought it was our best game,” Coach Adam Oates said. “I think by far it felt like we were the most ready to play a complete hockey game tonight.”

So after the 6-2 trouncing of the potentially potent New York Islanders at Verizon Center, the Capitals may be in a position to which they are fairly unaccustomed this season: with a chance to build real momentum. The victory was their third in a row and sixth in eight games, and it helped them both leapfrog the Islanders into second place in the Metropolitan Division and climb above .500. Their power play looked lethal, securing its spot among the best in the game, and the penalty kill — which thwarted the Islanders on each of their five chances — continued to show it could be considered top-flight, too.

“This is what we need to be every night and every practice,” said Nicklas Backstrom, who chipped in with three assists. “I think we can build off this. . . . It would be nice to get on a winning streak.”

Though there is tough competition ahead — Minnesota at home on Thursday, followed by road games against Western Conference heavyweights Phoenix and Colorado — Tuesday showed what the Capitals can be. They trailed 1-0 after the first period, and then took the game over.

Defenseman John Carlson opened the scoring by taking advantage of a sloppy Islanders’ clear, and then the goals came rapid-fire — almost corresponding to New York penalties. Ovechkin’s first of the night came just three seconds into a power play, off a faceoff win from Backstrom. Though the Islanders tied it up 17 seconds later, Johansson put the Capitals up for good, whacking in a rebound on the power play to make it 3-2 with 13 minutes left in the second.

“I just took a whack at it,” Johansson said. It didn’t matter how he scored, just that he did, and his addition to the score sheet put further emphasis on Oates’s mixed-and-matched lines for Tuesday, an exercise made necessary by Ovechkin’s return from a shoulder injury. Oates kept Marin Erat on the top line with Ovechkin and Backstrom, and put Johansson, who has spent most of his time at wing, in the center of the second line.

“I think I’m getting a little more used to it,” Johansson said. “The first couple games, it was a little different. But I think the more times I’ve played center, it feels better and better.”

Wilson, the 19-year-old the Capitals kept on the big club rather than returning him to juniors, created the next goal with a sprawling effort in front of Islanders goalie Evgeni Nabokov, a play that led to a slapshot for defenseman Alexander Urbom. And Ovechkin, feeling no apparent ill effects from the injury that kept him out of wins over Philadelphia and Florida, capped the five-goal second period with his 12th goal of the season — a tally that leaves him only behind St. Louis’s Alexander Steen.

“I feel great,” Ovechkin said. “I feel right away pretty fresh out there. Of course, have a couple days off, couple breaks. I feel good.”

As do, for now, the Capitals as a unit. The last 21 / 2 weeks have brought their only two three-game winning streaks of the year. Their power play is now scoring 27.9 percent of the time, a figure that by the end of play Tuesday was likely to be best in the NHL. They have killed 91.5 percent of power plays against them — again, a figure that was likely to top the NHL at night’s end.

It wasn’t perfect, and Oates is mindful of improving defensively. But for one night, at least, the good vastly outweighed the bad — and that could mean something going forward.

“A lot of good things that guys will feel good about themselves, so it should be a good practice tomorrow,” Oates said. “If we can play like that, that had a little bit of a look like last year to me. A lot of good things.”