Gone was Radulov's infectious energy, his dogged forechecking, his intense backchecking, his obvious joy in playing the game of hockey in the top league in the world after a four-year absence competing in the Kontinental Hockey League.

MONTREAL -- Forward Alexander Radulov missed two games last week because he was sick, and suddenly it seemed like the NHL-leading Montreal Canadiens were a different team.

The Canadiens, who are atop the NHL standings with a 14-3-2 record, lost each game Radulov missed, 4-3 in overtime to the Florida Panthers last Tuesday and 3-2 at the Carolina Hurricanes on Friday.

When he returned with two assists in a 2-1 win against the Toronto Maple Leafs on Saturday, the talk in the Canadiens room after the game was of a "Radulov effect."

That effect begins with Radulov's 16 points in 17 games entering the game against the Ottawa Senators at Bell Centre on Tuesday (7:30 p.m. ET; SNE, TSN5, RDS2, NHL.TV), but it does not end there.

Far from it.

Video: Alexander Radulov scores the game-winner

"All of us have been around people who have that energy and it's contagious, that upbeat, positive attitude," said Canadiens defenseman Shea Weber, who has known Radulov longer than anyone on the team from playing with him with the Nashville Predators. "I think guys feed off that.

"It's not an act. It's just who he is."

When the Canadiens signed Radulov to a one-year, $5.75 million contract on July 1, this was not the "Radulov effect" people were concerned about.

General manager Marc Bergevin did his homework before signing Radulov, 30, to that contract. He needed to make sure what happened the last time Radulov was in the NHL, when he broke curfew during the 2012 Stanley Cup Playoffs and was benched for two games by the Predators, was a thing of the past.

As it turns out, everyone's concerns, including Bergevin's, could not have been more misplaced.

"His energy, we knew about it," Bergevin said, "but it's off the charts."

Radulov's attitude has not only caused no problems for the Canadiens this season, it is probably his single greatest attribute.

After the game Saturday, Canadiens coach Michel Therrien mentioned how much Radulov loves to be at the rink, whether it's for practice or a game or even team meetings.

"Some people like classes, and some people don't like to go to classes in school," Therrien said Monday. "He likes everything. He likes classes, he likes exams, he likes to work to get to the exams. It's the same thing."

So how can Therrien tell Radulov enjoys meetings? Does he sit in the front of the class? Ask a lot of questions? Stand up and cheer?

"The eyes," he said. "The eyes tell everything."

The work ethic tells a lot as well, and you can see it after Canadiens practice when assistant coach Jean-Jacques Daigneault gathers the Montreal defensemen to work on point shots. Radulov joins them after every single practice, without exception.

On one such occasion, the Canadiens defensemen were gathered on the left point, taking passes from Daigneault and shooting.

Radulov wanted in on the drill, and he wanted in badly.

Every time the puck went from Daigneault to one of his defensemen for a shot, Radulov pivoted and got ready for a pass, his stick on the ice. When the defenseman shot instead, Radulov pivoted to face Daigneault, again with his stick on the ice, ready.

Finally, after this happened five or six times without receiving a pass, Radulov started banging his stick on the ice. He wanted a chance to shoot, but it's almost as if he was the little kid wanting in on his big brother's hockey practice and his brother's buddies weren't passing him the puck.

Canadiens defenseman Jeff Petry laughed when the scene was described to him several days later.

"Yeah, he's pretty much always out there with us," Petry said. "But when we're doing our [defensemen] drills, [Daigneault] never passes to the forwards.

"I don't think [Radulov] has really figured that out yet."

Nor would he care. Radulov would probably be there regardless, waiting for his turn to shoot.

Video: PIT@MTL: Radulov shows off patience to pad lead

"That's the time to make yourself better," Radulov said. "In a game, you've got to give everything you've got. In practice, you want to work on something you might need to do better, and that's what I'm trying to do."

That quote is very telling, because Radulov approaches every practice like it's a game, and that heightened intensity is very noticeable when it counts.

When Radulov gets the puck in the offensive zone, watch as defensemen try to get around his 6-foot-2, 205-pound body and take it from him. They simply can't.

Game after game, Radulov uses this ability to protect the puck in tight quarters deep in the offensive zone to create scoring opportunities for his teammates, and if he can't find one of them he creates one for himself.

His impact can be seen in the production of his center, Alex Galchenyuk, who has seven points in 10 games this season playing without Radulov on his wing and 12 points in nine games playing with him.

"The plays he makes at top end speed is unique," Galchenyuk said. "He does it every game."

Canadiens captain Max Pacioretty thinks Radulov's ability to protect the puck comes from playing on the big international ice surface in the KHL, and said he has benefitted from watching Radulov do it this season.

"I think when you see him do it and you see how much time and space he creates, it kind of carries over to your game and you realize there's more time out there than you think," Pacioretty said. "It doesn't look like it, but if you're able to take that first contact and still have control of the puck, you kind of put them in a vulnerable position defending and you're able to make a play.

"He's the best I've seen at it."

Couple that ability with an incredible work ethic, one that led Radulov to hustle and beat out an icing call while ahead 5-0 late in a game against the Detroit Red Wings on Nov. 12, and you have something the Canadiens have lacked for years, a true power forward who is able to attract defensive attention away from Pacioretty and give Therrien another legitimate scoring threat off the wing.

The work ethic, in spite of his prior reputation, is something Weber says Radulov has always had in him.

"He's always worked hard, always wanted to do the right things," Weber said. "He wants to win. When he gives up the puck he's going hard trying to get it back. It's just one of those things, he's always been like that.

"Maybe it's just getting noticed now."

It's getting noticed because Radulov is making it impossible to ignore, and in doing so is making a new name for himself in the best hockey league on the planet.