Unlikely.
I don't see us totally dropping the pressure forward role. Seeing how Rioli destroyed us in the Prelim, a forward with natural goal instinct may be better at than role that a hard tackling one who can't score. There is a good chance Ballas will take on the role if Mayne is dropped.
He's also one of RTB's favourites, there's no way he's getting the elbow any time soon.
Ballas will be fine, I just wish he and Son Son would stop falling over like they've been out of the piss all night.
As for Shane Yarran, I think he's been selected for his more mature body size as cover up forward. He'll really need to jump out in pre-season to get a game early doors. But there again I am not RTB or the coaching group, they may well have big plans for him.