Both players, the team's top two point men on the power play, could also miss Tuesday night's game against the Rangers in New York.
Markov and Schneider were injured in Montreal's 6-2 victory over the Maple Leafs in Toronto on Saturday night. Schneider has what the team calls an upper body injury while Markov is believed to have injured his right leg.
Doug Janik was called up from the club's AHL affiliate in Hamilton and was paired with Ryan O'Byrne. Janik was acquired Feb. 26 from Dallas, where he'd played 13 games.