"It's good for us to chip in," said Prust, whose third goal of the season put the Canadiens in front 1-0 early in the second period.
"Those top guys have been carrying a heavy load lately, and have been doing a great job. We want to contribute when we can. We were happy to do it tonight."
With the win, Montreal extended its win streak to five games and retained top spot in the Atlantic division. The Canadiens have only lost once in regulation time in the past 14 games and have not allowed more than three goals in any game during that time.
"Before playing this stretch, I won't lie to you, it scared us," Canadiens coach Michel Therrien said. "We should be very satisfied."
Prior to the game, Prust, Moen and White had a combined nine points on the season.
On Saturday, they had five points, and finished with eight hits, two blocked shots and no giveaways.
"We know what we're going to do out there the three of us," Prust said. "We're going to keep it simple, chip in pucks and support each other. We're good at protecting pucks. That's the key to our success."
After an uneventful first period in which neither team generated much offense, Therrien rewarded the fourth line by starting them in the second period.
"There was a message. We liked their intensity in the first period," Therrien said. "I don't think we had the right attitude to start the game. Those guys were intense."
Their line responded, scoring 19 seconds into the period.
Prust started the play when he stole the puck from Matt D'Agostini at the Buffalo blue line before passing it off to Moen. Moen quickly passed it to White, who completed the tic-tac-toe play by passing to Prust in the slot.
After Tyler Ennis evened the score later in the period, Moen drew two Sabres' players toward him, leaving Prust all alone behind the net.
Moen slid the puck to Prust, who waited patiently for Tomas Plekanec to walk into the slot. Plekanec's shot off the post and in at 17:44 put the Canadiens ahead for good.
"We get our success from putting pucks on net, playing that gritty type of game, getting to the net," Moen said. "It's always nice to pitch in offensively, get some points, and feel good about yourself. Tonight was that night."
Prust had a goal and an assist, Moen had two assists and White finished with one assist.
"They were practically our best trio," Therrien said. "They played a huge part in our team's victory. They created some scoring chances with their intensity. They spent a lot of time in the offensive zone. They certainly were true leaders tonight those three guys."
Therrien also complimented White's effort, suggesting he played his best game of the season. White has been in and out of the lineup for the Canadiens recently, sitting out six games as a healthy scratch since the start of the season.
"The biggest battle for me right now is for me to keep my confidence, not second-guess myself," White said. "I'm chomping at the bit every time I can get in there.
"I felt good. My line played well, made it easy for me. I just felt like I was really into the game, ready to go every time I got a chance to go out there."
The only goal the fourth line wasn't involved in was Alex Galchenyuk's game-winner, which he scored at 18:07 of the second period, only 23 seconds after Plekanec's.
The Sabres responded with pressure in the third, and rookie forward Zemgus Girgensons reduced the deficit at 4:04 after a great individual effort saw him control a bouncing puck, go around Canadiens' defender P.K. Subban, and beat Carey Price by poking the puck into the net.
The goal was a positive for coach Ted Nolan's Sabres, who have lost six straight road games and are last in the NHL with 14 points and a 6-22-2 record.
"He played well," Nolan said of the 19-year-old Girgensons. "I've known the kid now for three years and have watched him play, he does this all the time. It's one of those things that comes with maturity, he'll get better and better.
"Those are the building blocks with which we're going to turn this organization around. It's through people like that, with some strong character and will to get better."
Price stopped 23 shots for Montreal. He is second in the league with a .938 save percentage and hasn't allowed more than two goals in his past nine starts.
Rene Bourque, who missed the past two games with an upper body injury, was again left out of Montreal's lineup. George Parros and Francis Bouillon were healthy scratches. ... Montreal beat the Sabres 3-1 less than two weeks ago in Buffalo. The teams will meet twice more this season. ... The Canadiens take on the Los Angeles Kings at the Bell Centre on Tuesday.
Copyright by STATS LLC and The Associated Press
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