A defiant Dundee United first half side were unable to keep up the same fight in the second period, Bobo Balde scoring, following up Henrik Larsson's shot.
It went from bad to wrse for United, Jim Lauchlan saw red - sent off due to a terrible challenge on Larsson.
Henrik bagged the next goal, and Balde added a third in injury time, setting up the first of 2 Old Firm games in 8 days in March.
Bring on the Rangers!
Celtic:
Hedman - 7
Valgaeren - 7
Laursen - 7
Balde - 8
Smith - 6
Agathe - 6
Lambert - 7
Lennon - 8
Sutton - 7
Larsson - 8
Hartson - 7
Man of the Match: BOBO BALDE - His two goals set up a final with the huns!