The MLS disciplinary committee banned Osorio for kicking the ball directly to the side of the head of New York Red Bulls defender Kosuke Kimura, who had fallen to the ground. Kimura was not injured on the play.
The incident occurred in the 77th minute of New York's 2-0 victory last Saturday, which eliminated TFC from playoff contention.
Osorio appeared to be trying to clear the ball out of play when Kimura fell in front of him. No foul was called, but it sparked a brief skirmish on the field. New York's Dax McCarty was fined for violating the hands to the face rule during the melee.
The league ruled that Osorio's clearance attempt "endangered the safety of an opponent."
"It wasn’t intentional," Osorio said after the match. "They knew that, too.
"He was coming hard and I was mid-swing as he was falling. So unfortunately I hit him in his head. But he was OK and I said I was sorry."
Osorio will sit out games against Sporting Kansas City on Saturday and against D.C. United next week.
Red Bulls defender Jamison Olave was also fined for violent conduct from an incident with Justin Braun in the 45th minute of the same game that also went uncalled on the field.
De Santis continued Montreal's string of run-ins with the referees when he got one game for "continued aggressive, confrontational and irresponsible behaviour" toward officials following a 2-1 loss at home to the Columbus Crew last Saturday.
It was a first suspension this year for De Santis, but first-year coach Marco Schallibaum has been suspended four times for a total of five games.