It’s the first game in February – only one more full month to go in the NHL calendar before the playoffs begin. Game No. 50 of the season against Toronto. Thirty-two to go until April 9. The playoff push. The second season.

Tuukka Rask is back in net with Malcolm Subban as the backup after being recalled from Providence to spell the loss of Jonas Gustavsson. The veteran Gustavsson is cleared to practice but not play after an elevated heart rate.

Riding shotgun with Subban up Route 95, David Pastrnak back from his AHL rehab after 18 games with the Bruins — and ready to resume his second-half play that last year was among the best in total points. That effort got the 19-year-old Czech Republic native named the Seventh Player Award.

“Every time we come back from an All-Star break,” Claude Julien said Tuesday morning, “usually hockey gets pretty interesting during that second half.”

Here’s what we learned after Boston coughed up a two-goal lead – then the game in the 4-3 loss to their Original Six rival

Rust removed 9:37 into the game

“If there’s a little bit of rust in us,” Julien said pregame, “I would imagine it will show a little bit at the beginning.”

Sixteen seconds after a Boston power play — and withstanding a goaltender interference call by Toronto coach Mike Babcock — Brad Marchand’s 20-footer past Reimer with Matt Beleskey and Jimmy Hayes assisting stood up for the 1-0 lead.

The tally was Marchand’s team-leading 21st of the season

“It’s a good thing we have him,” Julien said of Marchand, “because he’s one of the consistent ones when it comes to that department.

Hayes tallied his second point in his last nine games, while Beleskey begins to heat up with his fifth point in three of his last seven.

Did that first goal bode well for the outcome?

Boston was 16-3-0 when leading after the first period; Toronto was 1-13-4 when allowing the first goal.

When former UNH standout Daniel Winnik scored at 9:56 of the second period that stat was held in balance.

Fifty-five seconds into the third period, David Krejci sent a pass across to Marchand for the easy redirect past Reimer. Then just 26 seconds later, Krejci nuzzled one past Reimer in a goalmouth scrum for the 3-1 lead. Pastrnak picked up two points in short order.

Rask rust

Tuukka’s lifetime log vs. the Leafs was 14-3-1 with a 1.81 GAA into Tuesday’s contest. At 3-1, Leo Komarov scored for the Leafs at 9:02 after Rask got confounded around his net losing sight of the puck. Then Kadri tipped a Komarov shot from the point at 11:31 to even it up at 3-3.

“Three of the goals were tipped in,” Julien said in veiled defense of Rask. “So that’s, to me, it’s poor coverage.”

“Well,” Rask said about Toronto’s penchant for tip-ins and his lack of adjusting, “you try to be as patient as you can. At some point, you have to react to the shot.”

In OT – with an odd power play at 4-on-3 – Pierre-Alexandre Parenteau stuffed it by Rask for the game winner at 3:06.

Special teams sputter

Boston’s second-best power play in the NHL went 0-for-4, while its penalty-killing units have given up a goal in each of the last three games after going nine games without yielding a power play goal.

Check of the game

At 8:20 of the second period, Marchand broke in 3-on-2 on Reimer. When he curled between the faceoff circles to make a play, Kadri leveled Boston’s antagonist with a textbook shoulder check – that Marchand never saw coming.

Is Claude shifting to consistent lines?

Boston’s coach has juggled more lines in his career than late night hosts Jimmy Kimmel and Jimmy Fallon combined. Tuesday night, he shifted course rolling out a consistent top-3 set of Marchand-Bergeron-Connolly, Eriksson-Krejci-Pastrnak, and Hayes-Spooner-Beleskey.

Two-goal collapses

At first count, Tuesday’s loss at home after leading by two goals was the Bruins’ fifth of the season. The loss puts the Black and Gold at an alarming 11-13-3 on TD ice.

“We go out there in the third, and determined to win. We score two goals, and then we turn around, and we get sloppy again,” a frustrated Julien chimed.

The Penguins, Flyers and Devils all won Tuesday night – teams behind Boston in the playoff push.

Next up is a back-to-back affair with the Sabres, making three consecutive games to begin the second half against teams well below Boston in the standings. Should be gimme points for any playoff-bound team.

“I don’t know if it’s relaxing, or losing focus,” Julien said about losing games – and precious points. “But certainly not good enough right now for our hockey team to think that we can contend if we keep making those kind of mistakes.”