It’s the the longest rivalry in the history of the NHL. And it resumed Saturday night when the high-flying Montreal Canadiens and the rebuilding Boston Bruins squared off for the 730th time and the ONLY appearance for the archrivals at TD Garden this entire season – unless the two meet in the postseason. The schedule makers have Gillette Stadium and The Winter Classic as the marquee game of the season between the two on New Year’s Day.

The 4-2 loss showed a better overall performance delivered Saturday night, thanks to the penalty-killing efforts after Thursday’s 6-2 whipping by the Winnipeg Jets.

But the painful learning curve continues for Boston’s young defense, once again without captain Zdeno Chara, and an anemic offense that was facing reigning Vezina Trophy winner Carey Price.

In head-to-head matchups, Price entered the game with a career 21-8-3 record and a 2.33 GAA; Tuukka Rask well behind at 3-13-3 and a 2.73GAA.

Montreal had won the last five straight against Boston.

Make that six.

Thursday night, Boston kept clean of the penalty-box pine.

Against the Canadiens, quite the opposite. Matt Beleskey was whistled off just 1:14 in. It took only 10 seconds for the Habs to take the 1-0 lead when David Desharnais converted on Rask’s doorstep. Julien using Brad Marchand and Patrice Bergeron on the first penalty kill of the season.

“I think for the most part I was pretty steady with my pairings,” Julien said postgame about his veterans picking up the charge when short-handed. “Kelly and Eriksson have been killing together since last year; Bergeron and Marchand, but we had Talbot there and Krejci who can kill as well, and there’s other guys in a pinch that I can use also.”

After that first power-play goal, primarily Bergeron and Marchand, and Kelley and Eriksson led the charge reeling off seven consecutive penalty kills.

“After that first, one, [the PK] was yeah real good,” Tuukka Rask said. “But we came back with a strong penalty-kill.”

Montreal went on its second man-advantage at 5:24. Bergeron and Marchand once again with Chris Kelley and Max Talbot successfully killing that penalty.

Then at 9:40, matching penalties put the 4-on-4 on display. David Pastrnak missed a golden opportunity to knot the score at 11:14 when he had Price dead to rights, but could not elevate the puck over Price’s pads from six feet out.

At 15:28, Torey Krug got two for tripping. Kelly and Eriksson again on the PK, followed by Bergeron and Marchand, who turned a take-away into almost a payday on Price.

The second period started more traditionally – and not in Boston’s favor – when Alexander Galchenyuk, Alexander Semin and Lars Eller backed the Boston D-corps into Rask, playing tic-tac-toe with Eller taking toe to the bank past Rask for a 2-0 lead.

At 13:30, a Bergeron backhand past Price was called off on a goaltender interference call on Loui Eriksson.

“First of all when you look back at it,” Julien said about the disallowed goal, “both his feet are outside the crease area, he got the inside position and then I felt that he was being pushed into their goaltender and even made that effort to get out.”

Only to be followed by an Eller bullet past Rask at 7:43 for a three-goal bulge. In the past 3-plus periods to that point, Boston had been outscored, 9-1, in two games.

The Garden breathed life when Matt Beleskey redirected a David Krejci roller along the crease past Price at 14:26 with Pastrnak also assisting.

Montreal went on its fifth PP at 3:30; complements of a 5-minute major and game misconduct to Ryan Spooner. Kelly and Eriksson again on the PK pairing, followed again by Bergeron and Marchand.

Then a sixth with a 5-on-3 for 1:01 when Marchand was whistled off.

But Boston kept it a two-goal game into Montreal’s seventh man-advantage at 11:16. Julien pulled Rask with two minutes to go to no avail, Tomas Plekanec potting an empty-netter at 19:06 before Bergeron got his first of the season on the power-play at 19:29 for the 4-2 final.

“That wins you hockey games – special teams,” Krug said after logging a team-high 23:05. “You gotta kill those penalties and it definitely held us in the game for sure. Maybe we keep that first one off the board and it’s a different game.”

“We’ve got to get better in certain areas,” Julien said.

Penalty killing is not one of them for now.

What was learned in Game 2…

 …Claude Julien will likely shuffle his young defensemen in and out of the lineup. Colin Miller – acquired in the Milan Lucic trade – replaced Zach Trotman for his first NHL game.

…Ditto for the 4^th line with Max Talbot starting Saturday in place of Zac Rinaldo.

…Newcomers Jimmy Hayes and Brett Connolly have no points and a combined minus-8 after two games.

…Boston struggles without the lead.

…Boston’s power play is 0 for 7 after two games.

…Adam McQuaid is solidifying his blue-line presence, and is the only defenseman with a plus-rating after two games.

…Chris Kelly will likely be an integral part of the penalty-kill combinations.

Kudos to Condon…Needham’s Michael Condon had the best seat in the house Saturday night. The pride of his hometown, and Belmont Hill, and Princeton University is the backup to Vezina Trophy winner Carey Price. Condon parlayed a stellar career at the prestigious prep school into a four-year ride in New Jersey from 2009-2013, before climbing the ladder from the NCAA to the ECHL to the AHL to the big sheet. Condon played 44 games for the Hamilton Bulldogs last year with a 2.44 GAA, good enough for a rookie run this preseason that landed him with that seat the end of the Montreal bench.