Devante Smith-Pelly’s third-period tally was the final goal in Washington’s 3-1 victory over Vegas in Game 3. (Ricky Carioti/The Washington Post)

Washington Capitals Coach Barry Trotz initially “wasn’t a fan” of free agent addition Devante Smith-Pelly. The 25-year-old was joining his fourth NHL team in seven seasons when he arrived in Washington, the remainder of his contract having been bought out by the New Jersey Devils, and there must have been a reason. In their first conversation, Trotz told Smith-Pelly how he could evolve from an inconsistent journeyman to an organization staple. Less than a year  after that chat, Smith-Pelly has made a fan out of Trotz and many others.

On Saturday night, in Game 3 of the Stanley Cup finals, Smith-Pelly dragged a pass from center Jay Beagle across the crease and lifted it over Vegas goaltender Marc-Andre Fleury to all but secure the Capitals’ first Stanley Cup finals home win in franchise history. He skated by the glass, his arms triumphantly outstretched, and screamed at the overjoyed red-clad fans cheering him from the Capital One Arena stands, another high in a year he described as a “roller coaster.”

“Starting from the summer and signing here, having to make the team out of camp, it’s been a roller coaster,” said Smith-Pelly, who has five goals in these playoffs. “But at the same time, it’s been — I’ve had a lot of fun, too.”

The expansion Golden Knights refer to themselves as the “Golden Misfits,” embracing that they’re a cast of characters other teams underappreciated and let slip away. But along with superstars Alex Ovechkin, Evgeny Kuznetsov and Nicklas Backstrom, the Capitals have similar castoffs in their lineup, players who came to Washington for a fresh start and to revive their careers. Those unheralded depth additions, busts on previous teams and question marks as the season began, have provided the Capitals consistent secondary scoring during this deep playoff run.

“Kudos to the new guys that are on our team this year,” defenseman Matt Niskanen said. “It was a process from the beginning of the year. A lot of people doubted whether we had the personnel to be any good this year. I think everybody within our team saw the potential, and we just had to keep working at it. Everyone kept a good attitude throughout the year, kept working, and we got better. Boy, some guys have played really well up and down the lineup. I think our top guys are leading the way, but at key moments this spring, we’ve got a big goal or a big [penalty] kill — different things like that from guys on the fourth line, third line. That’s what you need. It’s all about everybody contributing within their role. That’s what good teams do.”

Consider that the Capitals’ bottom-six forwards include Brett Connolly, a first-round draft pick who landed in Washington after the Boston Bruins decided to cut ties with him. There’s Chandler Stephenson, a Capitals prospect who didn’t make the team out of training camp and then was passed on by 30 other clubs after getting waived. Washington’s lone regulation goal in its clinching Game 6 overtime win in the second against the Pittsburgh Penguins came from Alex Chiasson, who spent the summer without a contract and signed with the Capitals after arriving in Washington on a tryout agreement. Smith-Pelly was inked to a two-way deal, meaning there was at least some doubt that he would make the opening night roster. The blue line has featured Christian Djoos, an undersized seventh-round pick, and Michal Kempny, a trade-deadline addition who was scratched for half the season in Chicago before getting dealt to the Capitals.

This is the group that was tabbed to collectively replace skilled forwards Justin Williams and Marcus Johansson, both 20-plus goal scorers, as well as slick-skating defenseman Nate Schmidt, after salary cap constraints and the expansion draft forced their departures. Washington’s “misfits” have scored 14 goals this postseason with Smith-Pelly’s Game 3 strike the latest.

“All through the playoffs, any team that’s having success, you’re going to have your depth come into play,” Trotz said. “A lot of times your stars get canceled out a little bit, so it’s your depth, your unsung heroes that make a difference.”

Secondary scoring was an emphasis for Washington since Pittsburgh’s third and fourth lines were the difference in a second-round series between the teams a year ago. But the Capitals’ depth seemingly took a step back before this season when proven veterans were replaced with rookies and inexpensive fringe players, outside expectations lowered so much as a result that many projected Washington as a borderline playoff team. Smith-Pelly, Stephenson and Djoos are on league-minimum contracts with $650,000 cap hits. Chiasson signed a one-year, $660,000 deal. Kempny’s contract is south of $1 million, and Connolly is in the first year of a two-year, $3 million deal. For a team that consistently spends to the upper limit of the salary cap, identifying cheap players with potential is a necessary art.

“There was next to no pressure on me to have to score or have to produce every single night,” Connolly said. “I just got to go and play. I think that helped me last year, and it’s helped me this year as well. . . . Same thing with [Smith-Pelly and Chiasson]. The guys just kind of welcome you with open arms and make it a really comfortable place to just go and play and do your best. It’s been a good fit for me, a good fit for those guys.”

That could by why the Capitals are two wins away from getting their names on the Stanley Cup, a trophy that doesn’t discriminate. Whether you’re a superstar or an oft-overlooked fourth-line forward, you get engraved in silver.

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