Kadri was suspended by the NHL on Thursday for goaltender interference stemming from his hit on Minnesota's Niklas Backstrom in the Wild's 2-1 shootout win Wednesday night.
That compounds Toronto's already problematic situation at centre as the club is already missing injured forwards Tyler Bozak and David Bolland.
Bozak, the Leafs' first-line centre and top faceoff man, has been out since injuring his hamstring in a road game Oct. 25 versus the Columbus Blue Jackets.
Bolland, acquired from Chicago in the off-season, had six goals and four assists in 15 games before suffering a severed tendon during a Nov. 2 game in Vancouver.
Kadri, along with converted winger James van Riemsdyk, was supposed to fill the void left by the injured centres. But he put his team in a deeper hole when he hit Backstrom in the head in the first period of Wednesday's game at Minnesota.
Kadri tipped a Joffrey Lupul shot on goal, then ran into Backstrom while driving to the net after the goaltender made the save.
Backstrom stayed in the game briefly before being replaced by Josh Harding. The team says Backstrom has an upper body injury.
Kadri received a minor penalty for goaltender interference on the play.
NHL senior vice-president of player safety Brendan Shanahan acknowledged driving the net is part of the game and contact with goaltenders happens as a result. But he said the hit is worthy of a suspension because Kadri was in control when he made contact with Backstrom and didn't make a reasonable effort to avoid the goaltender.
Shanahan also noted the hit was a forceful blow to the head that caused an injury.
He did agree with Kadri that there was no intent to injure on the play.
Later, Kadri received a match penalty for hitting Minnesota's Mikael Granlund in the head.
Kadri, who has 14 points (five goals, nine assists) in 18 games this season, will forfeit US$44,615.37 in salary.