Rangers center Filip Chytil sets before a faceoff against the Ducks...

Rangers center Filip Chytil sets before a faceoff against the Ducks in the first period of a game at Madison Square Garden on Dec. 18. Credit: Kathleen Malone-Van Dyke

ST. LOUIS — Rangers coach David Quinn followed through on his idea of pulling 19-year-old Filip Chytil on Monday night. The 2017 first-round pick was scratched for the first time in his career and replaced by Boo Nieves.

“It was an easy decision, really,’’ Quinn said of sitting the Czech, playing in his first full season. “Part of development isn’t just throwing people out there and letting them play. Part of development is learning accountability and learning that certain things are just non-negotiable, and he and I have talked about that. He’s let a few things slip in his game that just can’t happen. And sometimes it’s good to sit out and observe.”

Quinn said many of the same things when he scratched Lias Andersson, 20, on Dec. 14 against Arizona. Andersson also was a 2017 first-rounder.

“[Chytil is] a young player who’s learning the things that he’s going to have to do that he’s never had to do before,’’ Quinn said. “And it’s just a long season for a 19-year-old. There’s a lot of things that go into that, and he’s handling it well. He understands what we’re looking for and there’s certainly a lot of clarity in what we’re looking for. And he’ll be better for it.’’

Chytil (six goals, seven assists) had played in the first 37 games. Five players — forwards Mika Zibanejad, Kevin Hayes, Chris Kreider and Jimmy Vesey and defenseman Marc Staal — have played in all 38 games.

Shattenkirk back in

With Kevin Shattenkirk returning to the lineup, Brendan Smith was scratched to make room. That meant the defense had the unusual look of four righthanded shots (Shattenkirk, Neal Pionk, Adam McQuaid and Tony DeAngelo) and two lefties (Staal and Brady Skjei). Smith and Fredrik Claesson, the other scratched defenseman, are lefty shooters. DeAngelo played on the left side, partnered with Shattenkirk.

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