There was a time when Ryan Callahan arguably was the most effective player on the Rangers’ power play, the captain getting to the front of the net and banging home loose pucks with abandon. As a matter of fact, going back to the 2010-11 season, 33 of Callahan’s 76 goals (43 percent) have been on the power play.

But since his return from a knee injury, Callahan has been left off both man-advantage units, watching as the Rangers have turned what in recent history has been a sore point and turn it into a strength.

“Just before his first game back, I told him we were going to ease him in,” coach Alain Vigneault said after Saturday’s practice, his team preparing for Sunday night’s game against the visiting Flyers. “Because he missed quite a bit of time with the knee injury and he didn’t have a lot of practice time. But right now, both of our units are playing so well that we can’t really break them up right now.”

Callahan was injured Dec. 10 and missed nine straight games, returning to action Jan. 3 in Pittsburgh. Since the start of the team’s 2013-ending road trip Dec. 27 in Washington, the power play has gone 9-for-26 (34.6 percent) over the past eight games and the Blueshirts climbed their way into being the sixth-ranked man-advantage in the league at 21.4 percent.

“It’s one of the areas we spend a lot of time on because it’s so important,” Vigneault said. “Good power play is good personnel. You need a skill set, but there [are] also certain things as far as establishing the shot, making sure you have a net presence. Those are some of the things we put an emphasis on.”

Although Vigneault said he would like to keep an extra forward around, he has no plan on making a recall to replace J.T. Miller, sent down after Friday’s 3-2 home win over the Stars so Miller could play for AHL Hartford in their Saturday-Sunday back-to-back. That left the coach with just 12 forwards.