The Edinburgh club were dealt a blow on Friday when skipper James McPake was ruled out of the Hampden clash after struggling with a back problem.
His absence is likely to pave the way for 19-year-old Forster to have a major part to play having impressed after starting the last three games for Hibs - including his first senior start in the Edinburgh derby.
On the loss of McPake, boss Pat Fenlon said: "It's a big blow. Losing players and losing your captain is a big blow but we've got players there. Young Jordon has come in and been fantastic for us in the games he has played so we will just have to get on with it. These things happen in football.
"It's more of a blow for James, it's hard for him to take, to miss the cup final. We've got to make sure that we give him a chance to enjoy it after if we can."
Hibs may be without their skipper for the end of season showpiece against the Hoops, but they head into the cup clash with their confidence bolstered by three wins in a row over Hearts, Kilmarnock and Dundee.
Fenlon said: "Once we got our place in the final, it was important, in the five games we had left in the league, that we got momentum. Fortunately we have drawn two of them and won three and the players go into this game with big confidence."
Hibs will be aiming to end a 111-year wait to lift the Scottish Cup, with their lack of success in the competition also dominating the build up to last year's final against city rivals Hearts, which ended in a 5-1 defeat.
Fenlon said: "The only way to stop people from asking the question is to win it. It's as simple as that. It's the only way to put it to bed and we've got to try to do that.
"We can't do anything about what has gone before but we've got a great chance and that's something for myself and the players to embrace and enjoy."
- Sports & Recreation
- Pat Fenlon