The intensity of NHL playoff hockey is foreign to some Ottawa Senators players but head coach Paul MacLean is leaning heavily on the veterans that have been through the playoff wars before.

IN DEPTH | CBC's wall-to-wall coverage of the Ottawa Senators playoff run.

The Sens hopped off a Via Rail train in Montreal Tuesday evening and practised in nearby LaSalle, Que., Wednesday.

They arrived in "La Belle Province" early to prepare for Game 1 in Montreal, which can be seen Thursday night at 7 p.m. ET on Hockey Night in Canada.

This is the first time Ottawa and Montreal have played against each other in the playoffs in modern NHL history. The franchises last met in 1928.

At the Dollard-St-Laurent sports complex Wednesday, the speed and sharpness at practice was higher than the day previous in Ottawa. There was a sense of urgency, especially when it came to improving the powerplay.

Both powerplay units worked together and defenceman Erik Karlsson, who returned a week ago from a torn Achilles' tendon, said like most playoff series, special teams will determine the winner.

That means the Sens are counting on rookies Mika Zibanejad and Jakob Silfverberg, and possibly Patrick Wiercioch (if he plays) to boost the second powerplay unit.

Karlsson, who is still just 22 years old and anchors the team's top powerplay unit, said he knows Montreal can be a tough place to focus.

But he added the time spent in Montreal before Thursday's game is important for the newer players to feel comfortable in their surroundings and enjoy the playoff experience.

"We wanted to come a day early and have a nice team dinner and have the feeling because it is a special time," he said. "We should enjoy this."

Captain Daniel Alfredsson has missed the playoffs only twice in his 17 NHL seasons. The 40-year-old also missed just one game this season as the team went without top players Karlsson, Jason Spezza, Milan Michalek, Craig Anderson and Jared Cowen.

Everyone but Spezza has returned to the lineup, but Alfredsson said the rookies continue to be an essential piece of the winning puzzle.

Captain urges caution

Experiencing Montreal on a nice spring day will help them acclimatize to the playoff atmosphere in a hockey-mad city, he added, but stepping on the Bell Centre ice Thursday will require increased focus.

"It's going to be really loud. It's easy to get too jacked up, maybe. Just control your emotions. Take deep breaths and I think the easiest part is once the puck drops," he said.

"It's everything leading up to that point that gets you carried away sometimes."

Paul MacLean admitted he learned a lot about new players such as Eric Gryba and Jean-Gabriel Pageau, whom he knew little about before this season.

Both rookies have been unlikely soldiers for the Senators, helping their league-leading penalty kill down the stretch, especially.

This after Gryba was low in the depth chart among defenceman and Pageau was just fighting to make the Senators’ farm team in Binghamton at the start of the year.

But they have proven themselves on the ice, MacLean said, and the veterans have been important mentors.

NHL playoff hockey is different, though, he added, and players like Alfredsson, Chris Phillips, Sergei Gonchar and Chris Neil will have to continue to lead in the hostile atmosphere that awaits them Thursday.