Matt Niskanen’s third-period goal Monday didn’t stand as his sixth winner of the season. Not hardly. It wasn’t even significant to the outcome. Not when the Penguins got smacked by the Florida Panthers, 5-1. But it was Niskanen’s seventh goal, matching his career high with 33 games remaining this season. Niskanen, 27, has rounded into a reliable, versatile defenseman for the Penguins, but he’s not categorized as an offensive defenseman. He has, however, developed a knack for getting shots through what can be a minefield of sticks, legs and bodies in front of the opposing goaltender. Going into a game tonight against the Montreal Canadiens at Consol Energy Center, Niskanen has equaled the seven goals, 26 points he put up in a stellar rookie season (2007-08) with Dallas. He has at least one point in 12 of the Penguins’ past 14 games. He had no winning goals that rookie season, and only four through his first six seasons. His five this season have him leading the Penguins and all NHL defensemen. Niskanen was a first-round pick by the Stars in the 2005 NHL draft and was something of a sensation that rookie season, which he started as a 20-year-old. His plus-minus was plus-22. He upped his point total to 35 the next season, but his plus-minus plummeted to minus-11. Things sputtered some for him until the Penguins traded for him in February 2011. This season, he is not only on pace for his best season offensively, but he also was tied for the league plus-minus lead at plus-25 before games Tuesday. Asked to explain how he is getting shots through — and past the goalie —Niskanen deferred to the Penguins’ overall plan of having forwards feed the puck to defensemen as a way of opening things up a little. “Just the way teams play defense now — everyone packs it in around the net —it’s tough for forwards to create space or have space to do anything on their own,” Niskanen said. “You have to spread them out a bit.” Even then, it can be difficult to launch a shot that isn’t blocked or stopped by the goalie.