Defenseman John Moore, who missed the past six games recovering from a concussion, will replace McDonagh, who was injured Tuesday on a hit by Vancouver Canucks forward Alexandre Burrows in the Rangers' 3-1 win.
McDonagh, who is listed as day-to-day, is among the NHL's top-scoring defensemen with 14 goals and 29 assists in 77 games. He leads the Rangers in ice time, averaging 24:49 per game.
"I don't think it's going to be very long," Rangers coach Alain Vigneault said of McDonagh's absence after the morning skate. "His 25 minutes are big minutes against big lines and on the power play and penalty killing, so we're going to try and spread those minutes around, and I'm confident our group will be able to get the job done."