Nine. That is the amount the Bruins have been outscored by their opposition in the second period of their last three games.

Even in a game where they scored the first goal for the first time this season — and added a second first period goal to go up 2-0 after 20 minutes — the Bruins’ second period nightmares continued Wednesday night at Madison Square Garden.

The unraveling continued into the third as the Bruins fell 5-3 to the Rangers. Here is what we learned from the Bruins’ third straight loss.

Where it all unraveled

If there’s one moment where the tables turned, it would have been David Pastrnak’s high hit on Dan Girardi while the Bruins were leading 2-1. Pastrnak, who scored the first goal of the game 10 seconds in for his fifth of the season, earned a minor penalty for contact to the head at 10:55, and the Bruins got the brunt of the damage.

While the Bruins killed Pastrnak’s penalty, the Rangers’ response came to fruition late in the second when Kevin Hayes and Brandon Pirri (power play) scored 2:49 apart to give their team a 3-2 lead heading into the locker room.

Pastrnak will have a phone hearing tomorrow with the NHL Department of Player Safety. He has not had any prior history of supplemental discipline in his two-plus years in Boston.

Work in progress defense doesn’t help goaltending situation

With Tuukka Rask and Anton Khudobin both out due to injury, the Bruins D needed to show some sort of discipline in their own end over the last two games with Malcolm Subban and Zane McIntyre between the pipes. That obviously did not happen.

Both Subban and McIntyre allowed goals that they would love to have a second chance at no doubt. On Tuesday, Subban got yanked after allowing a one-timer by Ryan Suter from the point get past him on the low glove side. Over 24 hours later, McIntyre forgot to hug the post that led to Hayes banking a shot past him from behind the net for the equalizer.

The Bruins D, on the other hand, is a whole different story. Their blunders are magnified at least 10 times compared to McIntyre and Subban being thrown in the line of duty.

From Torey Krug allowing Rick Nash an easy entry to the doorstep on the power play to the miscommunication that led to Pirri’s two goals, the Bruins d-core showed that the work in progress is going to be a painful one.

All in all, the Bruins have allowed 14 goals in their last three games. That simply is not going to cut it.

Tuukka’s return needed sooner rather than later

Out for a third straight nursing a lower-body injury, the Bruins could’ve used Rask on a night like this. That’s not to say that he would have single-handedly solved all of their problems over the last three games, but certainly, it couldn’t have hurt.

Need any more evidence on how much the Bruins really miss Rask? Well look no further to his stat line in the first month of the season: 3-0-0, 1.67 goals against average and a save percentage of .947. The other three goalies — Khudobin, Subban and McIntyre — combined are 0-4-0 with a 4.50 goals against average and a .780 save percentage.

Perhaps Rask will return on Saturday when the Bruins continue their five-game road trip in Detroit. Either way, The Hub is collectively holding their breath that his injury is not serious.