— CapFriendly (@CapFriendly) February 24, 2022
Muzzin left Monday's 5-2 loss to the Montreal Canadiens during the second period following an awkward collision with Chris Wideman where the Maple Leafs defenceman appeared to hit his head on the ice.
The 33-year-old from Woodstock, Ont., did not play in Tuesday's tilt against the Columbus Blue Jackets.
Muzzin has 12 points (two goals, 10 assists) and is averaging 21 minutes over 41 games this season. He also missed seven games recently after sustaining a concussion during a match against the St. Louis Blues on Jan. 15 when he was hit into the end boards by Klim Kostin.
According to CapFriendly, Toronto placing Muzzin on the long-term injured reserve frees up $5.625-million in cap space with the NHL trade deadline just under a month away on March 21.
The Maple Leafs are third in the Atlantic Division with a 32-14-4 record and hold a three-game winless streak. Toronto next plays Thursday hosting the Minnesota Wild.