So much for the optimism Alain Vigneault had. As it turned out, Martin St. Louis’ right knee injury is a bit more serious than he let on. The Rangers’ third leading scorer is expected to miss 10 to 14 days.

Despite being streaky, St. Louis ranks second in goals (20) and third in points (47). Playing on the second line with Derek Stepan and Chris Kreider, he’s a valuable top six forward who also plays on the abyss known as the power play. His injury has forced Vigneault to adjust his lines and power play units.

With the offense cooling considerably despite Cam Talbot’s goaltending allowing them to win, Vigneault has reunited Rick Nash with Stepan and Kreider. Since missing a game against Calgary with neck spasms, Nash has slumped. He has two goals and two assists over the last nine games and no points in the last three. The team’s leading scorer has 39 goals and 62 points in 67 games. They need him to snap out of it.

Stepan is without a point in 10 straight entering tomorrow night’s home game against Chicago. It makes sense to put Nash back with Stepan and Kreider. Maybe that’ll get Stepan going. It’s not like he’s played poorly. He still is noticeable making the right defensive plays and doing a great job with Nash as the top penalty killing forwards. They’re a dangerous combo that’s combined for five shorthanded goals.

While that combo is back together, Vigneault has moved Kevin Hayes up to the Derick Brassard line with Mats Zuccarello. Hayes can play the left side instead of center. James Sheppard will center the third line with J.T. Miller and Carl Hagelin while the fourth line of Tanner Glass, Dominic Moore and Jesper Fast remains intact.

The powerless play gets a different look. Vigneault has opted for four forwards on the top unit. Keith Yandle and Brassard man the points with Nash, Stepan and Kreider up front. The second unit is more conventional with Ryan McDonagh and Dan Boyle on the points with Zuccarello, Miller and Hayes up front. At least they’re trying a different look. Until they become more aggressive instead of passive, it won’t matter. They pass the puck too much and never shoot enough. They also consistently get outworked.

Here is how the new lines look on paper:

Kreider-Stepan-Nash

Hayes-Brassard-Zuccarello

Hagelin-Sheppard-Miller

Glass-Moore-Fast

McDonagh-Girardi

Staal-Boyle

Yandle-Hunwick

Talbot

Skapski