As sharp as the Rangers’ offense already appears, they can’t count on scoring the six goals per game they have in their wins this season, so the back end can’t continue to allow an average of 3.3 goals per game. “We don’t want to give up four,” center Brandon Pirri said the day after the Rangers’ 7-4 win over the Sharks. “Some of those, it was unfortunate, we kind of left [goalie] Antti [Raanta] out to dry. We’re not gonna get seven goals every game, but if we’re doing the things we’re supposed to do in our own zone, it’s gonna reflect on what happens in the offensive zone.” Because of how well the Rangers are operating at a rapid pace, Henrik Lundqvist expects the team’s attack to continue taking advantage of odd-man rushes, but the faster play also may threaten to create similar chances on the other end. “You have to analyze the good and the bad,” Lundqvist said. “A lot of goals have been in transition, odd-man rushes, really. Obviously it’s something we talked about, how you can come back in your own end and sort things out, but I think in today’s game where you really get hurt and where you cash in [is] odd-man rushes. … That’s what we want to try and expose other teams [to] and it’s something we have to get away from ourselves. “It’s not something we’re looking to do, running up and down and exchange chances. We try to play a solid defensive game, but use our speed when we have the chance to create chances. … Coming back in our own end, it’s something we worked on and hopefully it pays off [Wednesday against the Red Wings].” Captain Ryan McDonagh didn’t practice Tuesday following the birth of his daughter, Falan. She is the first child for McDonagh, 27, and his wife, Kaylee. Defenseman Kevin Klein said he is ready to make his season debut Wednesday at the Garden. Klein had missed the past three games due to back spasms. … Left wing Pavel Buchnevich (back spasms) did not practice and is considered day-to-day after missing Monday’s game against the Sharks. … Dan Girardi (hip) also did not practice, but coach Alain Vigneault said the defenseman is “feeling a lot better” and the coach expects Girardi to begin skating again either Wednesday or Thursday. … Lundqvist is expected to return to net Wednesday after sitting out Monday’s win.