OTTAWA - Mike Cammalleri is holding the hot stick, but he credits Tomas Plekanec for the Montreal Canadiens' current hot streak.

"Plecks is playing really well. He's creating a lot and we're getting a lot of production as a result," Cammalleri said Tuesday night after he scored his fifth goal in three games -- all Montreal wins -- in a 4-1 victory over the Ottawa Senators.

Plekanec had three assists while Andrei Kostitsyn scored once and set up another.

The line of Cammalleri, Plekanec and Kostitsyn combined for six points and now has seven goals and eight assists in wins over the Boston Bruins, Philadelphia Flyers and the Senators.

Cammalleri also saved some praise for goaltender Jaroslav Halak, who stopped 45 shots in helping the Canadiens (15-14-2) win for the first time in three road games before a crowd of 18,866 at Scotiabank Place.

Halak was a big part of a penalty-killing unit that didn't allow a goal in seven power-play opportunities for the Senators (14-11-4), who are winless in five of their past six games and saw their five-game home win streak come to an end.

"He was the reason we won the game tonight, for sure," Cammalleri said of Halak. "The best penalty-killer is the goaltender, and he was."

Marc-Andre Bergeron, who also had an assist, scored the eventual winner on a second-period power play. Scott Gomez added an empty-net goal.

"The specialty teams were really the difference in the game tonight," said Montreal coach Jacques Martin after his team went 2-for-3 with the man advantage.

"Jaro came in and gave us a strong game. Everyone that played on the specialty teams did an outstanding job because we had a lot of penalties to kill."

Mike Fisher scored for the Senators and Brian Elliott, making his ninth straight start since Pascal Leclaire went down with a broken cheekbone, made 23 saves.

Ottawa was playing at home for the first time since Nov. 26. The Senators picked up just three of a possible 10 points on a recent five-game road trip. With the loss, the Senators fell to 10-4-3 at home.

"We got lots of pucks at the net, but just didn't do a good job of putting the puck in the net," said Senators centre Jason Spezza. "Some nights, the pucks go in when we get that many shots, sometimes they don't."

While the Senators were away, without naming names, team owner Eugene Melnyk said Ottawa needed more out of its star players. Spezza, who has just three goals on the season, is one of them.

"It didn't seem like the puck wanted to go in for anybody tonight," Spezza said.

Alex Kovalev, without a goal in 15 games, is another.

The former Canadiens forward saw his point-scoring streak end at three games.

"It's definitely hard for us to accept," Kovalev said of the loss. "We created a lot of shots and had a lot of opportunities, but their goalie played well for them."

The Canadiens lost the services of defenceman Jaroslav Spacek when he took a shot off the right leg at the end of the first period and didn't return. Martin said he'll be re-evaluated Wednesday.

Montreal also found themselves down a forward when Ryan White, recalled earlier in the day from the American Hockey League's Hamilton Bulldogs, was pulled out of the lineup after playing four shifts because the Canadiens hadn't informed the league of the move.

On the original lineup sheet, White's spot was taken by Matt D'Agostini, who was scratched for the game. White saw 3:13 of ice time before moving upstairs to the press box for the second period.

Had the Canadiens scored while White was on the ice, the goal would have been voided. Montreal is expected to have to file a report to the league explaining the matter, but otherwise there are no other consequences expected.

Although Carey Price had a relatively light night with just 15 shots in a 3-1 victory over the Flyers on Monday, he was given the night off in favour of Halak and the netminder was sharp throughout.

"(Martin) showed confidence in me to put me in net. I just needed to play my best game tonight and I did," said Halak.

He was the busier of the two goalies through the opening period as the Senators outshot the Canadiens 13-5, but Montreal led 1-0 after the first on Cammalleri's team-leading 17th goal of the season.

The Canadiens broke in on a 2-on-1 chance with Kostitsyn making a nice play to set up Cammalleri for a tap-in at 18:32. The Senators tied the game early in the second period when Fisher beat Halak with a backhander from close range, but Bergeron restored Montreal's lead on the power play. His shot from the point changed directions off a Senator and slipped past Elliott.

Halak came up with several big saves in the third to preserve the lead and, after Ottawa was whistled for too many men on the ice, Kostitsyn added some insurance late on the power play before Gomez scored with Elliott on the bench in favour of the extra attacker.

Notes: The Senators visit Philadelphia on Thursday while the Habs return home to play host to Pittsburgh. ... Defenceman Paul Mara and forward Benoit Pouliot were also scratched by the Canadiens. ... Blue-liner Alexandre Picard (upper body) and forwards Chris Neil (knee) and Ryan Keller weren't in the Senators lineup. ... Montreal improved to 3-2-1 in the second game of back-to-back contests this season.