Toovey, who is expected to undergo a traditional reconstruction after meeting with surgeon Julian Feller on Friday, suffered the injury in what appeared to be an innocuous stumble late in the fourth quarter.
Collingwood football director Geoff Walsh said there was "no sugar coating" the loss of the premiership defender, who has played 114 games.
"As a player, Alan's versatility and discipline have been important to us for a number of years and as member of our club there are very few, if any, people thought of more highly," Walsh said.
"That said, we're confident that Alan will bring to his recovery and rehabilitation the sort of professionalism he brings to his football and he will be back in very good shape."
Toovey, who received the Darren Millane Memorial Trophy as best clubman last year, has missed only nine of a possible 106 games since becoming a regular senior player in 2009.
Ben Johnson, a potential replacement on the half-back flank, is scheduled to return from calf soreness against Bendigo in the VFL on Friday night.
