The only way the Rangers were going to avoid being swept last night was if the Bruins fell down on the job.

And did they ever — literally, figuratively, every way.

What was your lowlight from last night? Was it Bruins goaltender Tuukka Rask tripping on the ice as a dribbler slid Buckner-esque by him and into the net? Was it Zdeno Chara allowing the Rangers’ Derek Stepan to sneak up behind him, take the puck and score a wraparound goal off a shocked, asleep-at-the-switch Rask? Was it a too-many-men call in the third period that set up the Rangers’ third goal?

We’ll get to the specifics in a moment, but first we need to get this out of the way: The Bruins put forth one of the worst efforts in the history of playoff hockey last night at Madison Square Garden, all but gift-wrapping a 4-3 overtime loss to the New York Rangers in what should have been the completion of a four-game sweep in the Eastern Conference semifinals.

Sure, you can go to the history books and find some truly one-sided beatings — for instance, old-timers remember the days of Orr and Espo when, in the spring of ’69, the B’s won back-to-back playoff games against the Toronto Maple Leafs by scores of 10-0 and 7-0 — but there’s a big difference between a mismatch and what happened last night.

The reality is that the Rangers scored one goal without help: Chris Kreider’s game-winner at 7:03 of sudden death.

It’s mind-boggling. The Bruins had taken a 2-0 lead and seemed poised to put the Rangers out of their misery. But then, as they have done so often, they showed their inability to close out a playoff series. Members of the vanquished Maple Leafs who watched last night’s game must have been asking themselves, “How did we lose to these guys?”

But let’s ask some real questions, starting with: So, what happened with Rask falling down like that?

“Yeah, I took a step to the side and, what I think, there was probably a skate mark or something and my skate dug in it,” he said. “Then I lost my balance, and the rest is history. It happens maybe twice a year in practice. I gotta be more focused, I think.”

So what is it, the bad Madison Square Garden ice or the lack of focus? All those of who think it was the bad ice, please raise your hands.

Anyone? Hello?

“Tough mistake,” Rask said. “Looks pretty bad on TV, I bet.”