But it remains to be seen what will happen now that Lars Eller, whose upper body injury prompted the moves, is close to returning to the lineup.
Eller skated without a "no contact" jersey for the first time on Wednesday since he suffered a suspected shoulder injury nearly two weeks ago.
He is not expected to dress when they play host to Anaheim on Thursday night, a game that will be marked by a tribute to former Canadiens captain Saku Koivu, who ended his career with the Ducks. But Eller is close to a return.
"I will let you know when Lars comes back," was all coach Michel Therrien would offer.
The 20-year-old Galchenyuk was a centre when he was drafted third overall by Montreal in 2012 but has played mostly on left wing in the NHL. He got a look at centre in the pre-season, but was quickly put back on the wing.
In three games since the Eller injury, he has been eye-catching while centring the first line with Max Pacioretty and Brandan Gallagher, playing with speed and intelligence and setting up several scoring chances.
He broke out with a hat-trick Tuesday night against Carolina, with Pacioretty assisting on all three goals.
"With Larry (Eller) being out, there's an opening and someone needs to step up and he's done a very good job of that," Gallagher said of Galchenyuk. "I know that me and Patch (Pacioretty) find him easy to play with because he's going to find you and make plays.
"We can be a really good line, but it's a matter of doing it night in and night out."
Since the change, the line has combined for five goals while the team has gone 3-0-0.
Pacioretty said it is key that Galchenyuk is developing into a strong two-way centre who can be a scoring threat without being a defensive liability.
"He's open minded and that's the most important thing; his willingness to learn," said Pacioretty, who leads the team with 13 goals and 25 points in 32 games. "Nobody in this league is perfect and we want him be a certain type of player.
"He's the future of this team. The way he builds up his game over time is important."
Meanwhile, Desharnais looks to be flourishing on the third line with P.A. Parenteau and Brandon Prust. He has a goal and two assists since the moves, including a clever pass against the grain to set up Prust's goal against the Hurricanes.
"He's great to play with," Pacioretty said of Desharnais, who has been his centre for most of the last few seasons. "Davy has a way of making people around him better.
"And Prusty's a great guy for that line because he brings a lot of energy and he's a straight-line player who crashes and bangs. They've been unbelievable these three games."
Being on the third line may help the diminutive Desharnais because he is not going against the opponents top checking unit and first defence pair every shift.
He has taken some heat from fans and the media, who say he's too small. He's had that since he joined the team as an undrafted try-out in 2008. But when he's on his game, Desharnais is a clever passer who doesn't shy away from the opponent's crease.
"Since the beginning of the year I thought I wasn't playing that bad," said Desharnais. "Now I'm in a different role and I'm feeling good out there.
"Of course, you don't want anybody to criticize you, but that's how it goes. You've got some haters and some people that love what you do. Of course I care, but I've got to do my job and focus on what I have to do."
Eller is at his best as a centre, but something will have to give when he returns. Tomas Plekanec has the second line centre job, while Manny Malhotra is a key pivot on the fourth unit.
Someone will have to move to the wing. Galchenyuk would be the prime candidate, but he looks to be making that choice more difficult with each strong outing.
Defenceman Mike Weaver, out three games with a concussion, is back to normal practising while rearguard Bryan Allen, who has missed five games with a virus, also is close to a return.
A week after the emotional funeral of Canadiens legend Jean Beliveau, another who spent 10 years as captain will be celebrated when Koivu takes part in a pre-game tribute.
The Finnish centre was a much-loved figure in 13 seasons with the Canadiens from 1995 to 2009. The 40-year-old played his last five seasons in Anaheim before retiring.
A highlight was Koivu's return near the end of the 2001-02 campaign after a successful season-long battle with abdominal cancer.
"I think everyone there that night could feel the emotion," said Therrien, who was in the first of his two stints as the Canadiens coach at the time. "He was a great captain.
"Through his determination, his professionalism, his work ethic and his actions, he was everything you want from a captain."
NOTES: The Canadiens assigned forward Sven Andrighetto to the American Hockey League's Hamilton Bulldogs on Wednesday. Andrighetto had three points (two goals, one assist) in four games with the Habs.