"We had a really good start, obviously," Canadiens coach Michel Therrien said. "There is a lot of positive about winning a hockey game here."
Moen's wrist shot beat Michal Neuvirth for his first goal of the season and first in 47 games at 8:53. A sloppy pass from Capitals defenseman Alexander Urbom to Mikhail Grabovski led to a turnover just outside Washington's defensive zone. Michael Bournival corralled the loose puck and quickly passed it to Moen.
Three minutes later, Desharnais scored his first goal of the season (snapping a 21-game drought dating to last season) when he deflected Josh Gorges' shot from the point past Neuvirth's catching glove. The goal went to review to see if Desharnais' stick was above the crossbar, but there was not sufficient evidence to overturn it.
Briere extended Montreal's lead to 3-0 on the power play at 13:40 when he was able to sneak behind Urbom in front of the net.
"We waited until about 18 or 19 minutes [remaining] in the first period to look like we had some jump," Capitals right wing Troy Brouwer said. "[We] spotted them a three-goal lead and things that we're trying to avoid: turnovers on the first one, taking penalties on the third one, second one's [a] tough call, but it's how it goes. We've got to have better starts. We can't expect to win games if we're down 3-0."
With time running out in the first period and the Capitals on the power play, Ovechkin scored on a tight-angle shot at 19:37. John Carlson's wrist shot missed wide and caromed to Ovechkin along the goal line to Budaj's right.
It snapped a streak of seven straight goals scored against Washington dating to its 4-0 loss to the Pittsburgh Penguins on Wednesday.
In the third period, Ovechkin, who had taken a roughing penalty two minutes earlier by knocking Brian Gionta to the ice after the two collided in the Capitals' offensive zone, brought Washington within 3-2 at 12:27 when he deflected Carlson's shot in the slot.
"I think we know what to expect from them," Budaj said. "They have great offensive power and a lot of skill up front. With [Ovechkin] playing the way he is playing, we were able to manage, and I think they only had one shot at the end, which was not a huge scoring chance. We got a big two points for us tonight."
Following the loss to the Penguins, the Capitals bemoaned a lack of execution and self-inflicted mistakes, problems that manifested themselves again Friday.
"Same mistakes," said a frustrated Adam Oates, who admitted he was more upset with his team's performance Friday than he was Wednesday. "Some mistakes from guys you don't expect, some mistakes from youth, and you know what, you've got to be good enough to survive them."
The Capitals are five points behind the Penguins for first place in the Metropolitan Division; Washington plays Saturday at the Toronto Maple Leafs.
The Canadiens have won two straight and three of four and sit fifth in the Atlantic Division, with a visit from the Penguins on Saturday.