Defenseman Calle Rosen was recalled from the AHL's Toronto Marlies In a corresponding move.
Muzzin exited Tuesday's contest against the Tampa Bay Lightning after taking a shot off his hand in the second period.
The 31-year-old has been one of the Maple Leafs' most important players in 2019-20. He's third on the team in average ice time (21:36), first in hits (109), and first in blocked shots (110). He's also chipped in six goals and 17 assists in 53 games.
Muzzin signed a four-year, $22.5-million extension with the Leafs on Monday.
Rosen, who was with the Maple Leafs before being dealt to the Colorado Avalanche last offseason, was reacquired prior to Monday's trade deadline. He's spent the majority of his time in the AHL this season, though he did record two assists in eight games with the Avalanche.