The Saints have soundly beaten all of their rivals.
The exception was Geelong which was a great, tight match. But even in that game the Saints were pretty convincing - they stuck to their game plan distressingly well even under all the duress that Geelong could deliver across the field.
I really can't see them getting beaten before the finals. And in the finals I think that probably only a fully fit and firing Geelong could trouble them. And Geelong's chances of being fully fit are very questionable at this moment in time.