Pressure and expectation does strange things. I've watched my team lose 4 prelim finals in 8 years (even if we weren't always favourites). Souths will be out to put them off their game and make them do silly things. About the worst thing they could do is mouth off or start any niggle. If they just play their footy they're tough to beat.
In saying that, it's all about defence for Souths. Our attack is sublime and our middle has been terrific all year, but our edges are shaky. Crichton and Yeo the big dangers IMO.
I think it'll either be a close win to the Rabbitohs or a big win to the Panthers.