While this is a tough tie for whoever makes it through, it is worth pointing out that Aberdeen knocked the SPL champions out at that stage last season. They nearly did it at Pittodrie - conceding a last minute goal - before knocking them out at Parkhead. Of course, they then suffered an amusing defeat to Queen of the South in the semi-finals, but it shows Celtic should not be feared.
Of course, there is still the small matter of the replay to contend with. Saints will face Motherwell at St. Mirren Park on Tuesday, February 10 - and it seems the game will not be shown live on Sky Sports.