Second-half goals from Joe Ledley, Georgios Samaras, Anthony Stokes and Scott Brown took Celtic past 10-man Dundee United and into the semi-finals of the William Hill Scottish Cup with a 4-0 victory at Tannadice.
The home side were on top before defender Robbie Neilson, previously booked for a foul on Samaras, was shown a straight red in the 28th minute for leading with an elbow in an aerial tussle with the Greece striker.
The game turned on that incident and in a one-sided second half, Ledley, Samaras and Stokes racked up an unbeatable lead before Hoops skipper Brown scored from the spot a minute from time.
United, unchanged and on the back of three successive wins, started confidently and in the eighth minute skipper Jon Daly got past Hoops stopper Charlie Mulgrew to get on to the end of a Willo Flood cross but headed past the near post from eight yards.
The game took a dramatic twist when Neilson had his moment of madness and there was little room for complaint from the United camp and Samaras resumed after treatment.
Almost inevitably Celtic forged ahead in the 52nd minute with the goal coming through Ledley. The Wales international was involved at the start of the move, and when striker Anthony Stokes went past United defender Sean Dillon and cut the ball back, Ledley pounced from six yards to whip the ball past Tannadice keeper Dusan Pernis.
Samaras secured his side's place in the semi-finals 20 minutes from time when he rose inside the United box to head in a looping Mulgrew free-kick.
With the Hoops fans still celebrating, Russell flashed a drive from 14 yards high over the bar when he should have hit the target.
In the 79th minute Stokes missed a sitter when he rattled the bar from eight yards after being set up perfectly by James Forrest, but there was time for the Irishman to make amends, latching on to a Ledley pass with four minutes remaining before slipping the ball past Pernis.
A minute from time Samaras won a spot-kick when he was tripped by Dillon inside the box and Brown converted the penalty to rub salt into the wounds of United, who were left bedraggled.