The play kept going, but Derick Brassard knew it was over. “The sound of the back post and the main post [are] different,” he said. “I felt like it hit the inside of the goal. But it really doesn’t matter.” No, it didn’t matter if it was Brassard or Benoit Pouliot in the aftermath, because the result was the same. The puck got behind Marc-Andre Fleury and into the Penguins’ net, overtime coming to a quick and dramatic finish as the Rangers were able to walk out of CONSOL Energy Center on Friday night with a 3-2 win in Game 1, drawing opening blood against the mighty Pens in this second-round playoff series. “It’s big for our team to come here and beat them the first game,” said Brassard, whose winner came 3:06 into the extra frame when he slid into the goalmouth, took a pass from Pouliot and fired a wrist shot up and over Fleury, rattling the top-back pipe. “It shows us we can play with those guys.” After Brassard’s shot went in, it quickly came out of the net and referees Brad Kozari and Brad Watson — who were fumbling throughout the entirety of the contest — let the play continue. “I kind of stopped playing,” Brassard said, speaking of his frantic waving towards the refs that his shot went in. Either way, the still-live puck eventually came back to him, he fed Pouliot in front, and the puck went in a second time, just for good measure. Two for one, and they’ll take it. “There’s nothing quite as euphoric,” Brad Richards said, “as winning in overtime.” For a long time, it seemed as if the Rangers would have been lucky to even get to overtime. They blew a 2-0 first-period lead by playing arguably their worst period of the postseason in the second, allowing the Penguins to outshoot them 15-4 and tie the game behind goals from Lee Stempniak and James Neal. “We just stopped skating,” said Richards, whose team has now played three games in four nights en route to what will be five in seven following their first-round Game 7 win over the Flyers on Wednesday at the Garden. “It was probably us settling into a 2-0 lead more than anything else.” That lead came by way of early tallies from Pouliot and Richards, neither goal exactly a feat of marvel as Fleury continued to show postseason cracks. Pouliot’s goal was a 55-footer that beat Fleury over his shoulder, and even though Richards was left wide open at the far post for his, Fleury was flailing around at the top of his crease, nowhere to be found when Richards calmly went to his forehand and slid it in.