The striker sustained the knee injury in the 2-2 draw with Fleetwood following a tackle from their club captain Mark Roberts which infuriated Shakers boss David Flitcroft.
He assumed the injury was a serious one in the immediate aftermath of last week's fixture and Flitcroft confirmed the news was bleak at the weekend, with Forrester possibly out until 2015.
"Anton is in a bad way", said Flitcroft. "When I saw the tackle, I saw a bad challenge. He's rolled him and you can tell when it's a nasty tackle.
"I don't think there was any intent in the challenge but it was certainly a nasty tackle and the way he has rotated on his knee, he has done his ACL & his MCL, so now he will be out for between six and nine months.
"I've spoken to Anton and he's a young lad that is trying to make his way in the game, but the saving grace in this is - Blackburn Rovers have one of the best physios in the country in Dave Fevre, they have all the right equipment.
"Anton could not be in better hands. We've been very professional in this and so have Blackburn.
"Now we just wish him well, he's phoned all the lads and sent them texts. The lad is gutted because he wanted to be a part of this until the end of the season.
"He has to have a real belief now and from the club we all wish him well and thank him for what he has done for us; his goals have been very important to us."
Forrester made 31 appearances for the Sky Bet League Two side this season, scoring seven times.