Tuukka Rask/By S. Bradley

Tuukka Rask/By S. Bradley

Did the Bruins get caught with dreams of Penguins in their heads?

It sure looked that way when you add up all the mental mistakes they made en route to an overtime loss to the New York Rangers in Game 4 of the Eastern Conference Semifinals Thursday.

Now instead of preparing for Pittsburgh or Ottawa, the Bruins will come home and get ready for Game 5 at TD Garden Saturday night.

For the most part, this wasn’t your typical Bruins failed-closeout performance. They peppered Henrik Lundqvist with 40 shots, scored two power-play goals and forechecked well. One player from each of the top three lines contributed at least one point and Torey Krug scored another goal.

So instead of a 60-minute “stink-fest” the Bruins went through just enough poor lapses to allow the Rangers back into this series.

If there was a positive development, it was the Bruins flushing the costly too-many-men penalty out of their system in Game 4 rather than waiting for Game 7 (sorry for the 1979 and 2010 flashbacks). With 8:55 elapsed in the third period, and the Bruins ahead 3-2 on the strength of Tyler Seguin’s first goal of the playoffs, the Bruins went down a man. Maybe Seguin was still celebrating that goal when he jumped on the ice too early, or Shawn Thornton was trying to provide material for the Merlot Line haters out there by not going off after he waved to the bench, but the bench-minor bug bit the Bruins again.

Brian Boyle scored the Rangers’ first power-play goal in seven games, as he snuck into the zone and Gregory Campbell had a rare lapse of judgment and dropped down too low in the zone on the penalty kill.

So the Bruins paid for another bench minor at a key time. They could’ve prevented a Game 5 by playing smarter in other situations, and they’ll have to clean up their act to keep this from becoming a long series.

Zdeno Chara twice blindly lost the puck to Derek Stepan, but it only cost him on the Rangers’ second goal of the game. Rask stopped Ryan McDonagh’s shot from the slot on the first Chara giveaway, but didn’t get back into his crease in time to have a chance to deny Stepan. The Rangers center picked Chara’s pocket and Dougie Hamilton failed to warn his partner of Stepan’s close pursuit. It would’ve been nice, however, if Rask had exerted himself to get back to his crease.

David Krejci lost an offensive-zone faceoff clean to Stepan before the game-winning goal. Krejci was 0-for-3 in the game against Stepan, so perhaps the Bruins should’ve gone with Gregory Campbell on the ice for the left-side draw. Or Krejci should’ve at least tied up the Rangers’ center better. Instead the Rangers flew down ice and Chris Kreider sealed a 4-3 win with a goal at 7:03 of the extra session.

All these miscues, and I haven’t even mentioned the only error that’s going to lead the highlight reels across the continent and beyond. Rask’s plop onto his rear on Carl Hagelin’s goal – the score that awoke the Rangers and Madison Square Garden – was the most glaring mistakes and the one that you could almost laugh at had it not cost the Bruins the way it did. But it was also the one you could excuse. Sometimes skates get stuck, sometimes players slip. After all, ice is slippery. It was a physical mistake, as opposed to the mental gaffes the Bruins made in other key situations.

Even after the Hagelin goal, the Bruins had the lead. They took the lead again in the third period. They didn’t have the mental fortitude to close this one out. They’re now 1-3 in closeout games this postseason. Rask’s record dropped to 2-8 with a chance to put a team away.

You can look at Game 4 and say the mistakes are correctable. You could also look at the Bruins’ loss and say there were too many correctable mistakes made by a team with a chance to end a series and get some rest before playing in the NHL final four. A real pessimist would look at the Kreider goal and remember it was a Simon Gagne goal in overtime that started Philadelphia’s historic comeback in 2010 against Rask and the Bruins.

Regardless of which way you’re looking at things, the pressure has just shifted a little toward the Bruins. To make sure they don’t have to go into full-on panic mode, they need to block out thoughts of 2010, the Penguins, the Senators and everything else except taking care of the little details that could shift Game 5 in any direction but their own.