Halak, who shut out Philadelphia 1-0 Friday, had 29 saves against the playoff-bound Sabres for his fifth shutout of the season.
"I'm definitely going to enjoy the moment," Halak told reporters, "but there's always some luck involved, too. The Sabres did hit a few posts."
The Slovakian Olympian became the first Canadiens player in four years to post shutouts on consecutive nights.
"I think everyone deserves credit," said Halak. "We just played two tough games and the guys didn't give the Flyers or the Sabres any good scoring chances. They were constantly blocking shots, they didn't give them anything."
Ryan O'Byrne, Tom Pyatt and Sergei Kostitsyn scored to keep Montreal in contention for a post-season berth.
O'Byrne, who scored in the first period, had not collected an NHL goal since March 2008. Pyatt had his second of the season.
"Having your goalie play the way Jaro is right now is big for all of us but especially for a defenseman," said O'Byrne.
"Knowing how strong he's been back there allows us to just make plays and not worry about him making saves.
"His confidence has seeped into all of our games I think."
Buffalo lead the Northeast with 96 points, with third-placed Montreal pulling within five points of No. 2 Ottawa (91).
Sabres netminder Ryan Miller finished with 35 saves.
Buffalo captain Craig Rivet was upset by his team's performance.
"It's pathetic," said Rivet.
"They (Montreal) played a playoff game and gave everything they had, and we looked like a bunch of guys that wanted to wait and hopefully win a hockey game."
The Canadiens' style had also hindered Buffalo, said Rivet.
"They do a very good job of clogging up their neutral zone," he noted. "They've got five guys in front of the puck all the time."
(Reporting by Gene Cherry in Salvo, North Carolina; Editing by Peter Rutherford)