The Washington Capitals weren’t intending to reshape their roster as the NHL’s trade deadline approached Monday afternoon. They had made a minor move the previous day, but as their closest competitors in the East Division loaded up, an opportunity presented itself.

So General Manager Brian MacLellan pounced, acquiring right wing Anthony Mantha from the Detroit Red Wings for wingers Jakub Vrana and Richard Panik, a 2021 first-round draft pick and a 2022 second-round pick. Mantha is signed through the 2023-24 season at a $5.7 million average annual value.

“We came into the deadline trying to make our team better,” MacLellan said Monday night in a video conference call. “How can we make it better? We talk about a lot of players, a lot of opportunities, who’s available, and we just kind of go from there. It wasn’t a conscious decision: ‘Let’s shake the team up.’ We’ve had a good year so far. … Things lined up, and this is what we ended up doing.”

Shortly after the Mantha deal became official, the Capitals also landed Michael Raffl from the Philadelphia Flyers for a 2021 fifth-round pick. Raffl, a 32-year-old winger who can also play center, had three goals and five assists in 34 games for the Flyers this year.

The Mantha deal was the biggest of the deadline and will have long-term effects for the Capitals (27-11-4, 58 points), who are in a tight battle atop the East Division. The Capitals, with 14 games left, were the last of the top teams in the East to make a major move at the deadline.

Boston traded for Taylor Hall, Curtis Lazar and Mike Reilly; the New York Islanders acquired Kyle Palmieri, Travis Zajac and Braydon Coburn; and Pittsburgh added Jeff Carter.

Mantha, 26, is a 6-foot-5, 234-pounder known for his scoring ability. He is able to play on both the left and right side and can fit in up and down the lineup. MacLellan said he will fit best with a playmaking center: Evgeny Kuznetsov or Nicklas Backstrom.

The Capitals had a conversation about Mantha with Detroit a few weeks ago, and the deal finally came to fruition Monday.

Mantha had 11 goals and 10 assists in 42 games for Detroit this year, coming off a 2019-20 season in which he scored 16 goals with 22 assists in 43 games. Since making his NHL debut in the 2015-16 season, he has 95 goals and 99 assists in 302 games.

“He’s a long player. He uses a long stick. He has a good shot,” MacLellan said. “The size factor more translates to skill than a physical running over people, and I think he had that in him. He’s a big, strong guy that can play a big game and uses his size and strength and length to his advantage. I think it’s an effective style on the ice.”

Raffl carried a $1.6 million salary cap hit, and his deal is up after this season. The Flyers will retain 25 percent of Raffl’s remaining salary. Mantha will be available to play for the Capitals on Tuesday night at Capital One Arena against the Flyers; Raffl will not be.

To add Mantha, the Capitals lost a younger, electric winger in Vrana.

The 25-year-old had 11 goals and 14 assists in 39 games for the Capitals this season. Vrana, who was part of the Capitals’ 2018 Stanley Cup title run, was set to become a restricted free agent due a considerable salary bump this summer. The upcoming contract negotiations were a factor in the deal, MacLellan said. Vrana was in the final year of a two-year, $6.7 million bridge deal.

Vrana, who produced no points in 15 games in the 2019 and 2020 postseasons, was selected by the Capitals in the first round of the 2014 draft and was a constant in the Capitals’ lineup the past three seasons until he was a healthy scratch for two games against the New Jersey Devils this month.

Capitals Coach Peter Laviolette expressed frustration with Vrana in recent weeks, suggesting his game needed a bit of a “reset.” In four games after sitting out two, he had one goal and one assist.

MacLellan said he felt Vrana and Panik were unhappy with their roles — Vrana in particular.

“Jakub’s a little frustrated with where he’s at here within the organization, probably wants a little more ice time, wants more responsibility, and there was a tug-of-war between coaching staff and staffs that have had him and the way he was playing,” MacLellan said.

Panik signed a four-year, $11 million contract with the Capitals in July 2019 and was a healthy scratch in three of the Capitals’ past five games before the team put him on waivers last week. He cleared and was shifted to the taxi squad — a move that gave the Capitals more salary cap flexibility at the trade deadline.

MacLellan admitted part of the reasoning behind sending Panik to Detroit was to get rid of his cap hit.

“It never seemed to click for him here,” MacLellan said. “He’s had periods where he’s played really well for us and then had other periods where I don’t think he got, in his mind, enough ice time and enough opportunity. So the trade for him gives him a chance to move up in a lineup and get more ice time.”

The two moves Monday came on the heels of Sunday’s trade of defenseman Jonas Siegenthaler to New Jersey for a 2021 third-round draft pick.

“He wanted to play, so I hope it is a good fit for him,” Laviolette said Sunday night of Siegenthaler. “He’s a terrific kid. … He worked his tail off, and I wish him the best, and I hope he has a good place in New Jersey where he can get going and play some games and have fun playing hockey.”

Washington looked at adding a goaltender at the deadline but decided it was confident in its two young players, rookie Vitek Vanecek and second-year goalie Ilya Samsonov. Neither has any playoff experience.

“Vitek has been pretty solid. Samsonov is improving and coming along,” MacLellan said. “So it is tough to bring in a guy and throw him in front of them.”