Freddie Woodman was the hero with a hat-trick of penalty saves as Aberdeen edged past Kilmarnock in a shoot-out to reach the last four of the William Hill Scottish Cup.
The on-loan Newcastle goalkeeper denied Eamonn Brophy, Greg Taylor and Greg Kiltie as the Dons sealed a 3-2 shoot-out win following a 1-1 replay draw at Rugby Park.
Stephen O'Donnell gave Killie the lead six minutes into extra-time but Kenny McLean soon levelled from the spot to set up the thrilling finale.
The Dons will face Motherwell in the semi-finals on April 14 but they will be without McLean, Graeme Shinnie and Shay Logan, who all picked up their second bookings of the competition.
The defeat was Kilmarnock's first in 10 matches since a league reverse at Pittodrie in January.
The home fans in the bumper 8,998 crowd received a pre-match boost when Jordan Jones was named in the Killie team after recovering from a hamstring injury.
Neither team seriously threatened in the opening quarter and it took a melee to liven up the game.
Rory McKenzie was eventually booked after he had sparked a mass confrontation with his repeated attempts to dig the ball out from a grounded Gary Mackay-Steven, who had annoyed the home crowd with a challenge on O'Donnell seconds earlier.
Aberdeen took the initiative as McLean came close from long range and Scott McKenna hooked over under pressure after a corner.
Kris Boyd was wide with a free-kick at the other end and Gary Dicker, McLean and Adam Rooney were booked before the break as the tie retained its edge.
The teams cancelled each other for 20 minutes after the break but Jones ignited the second half. The winger had a volley saved by Woodman before embarking on a run that saw both Logan and Ryan Christie booked for fouling him.
The hosts increased the pressure as Boyd looped a header just over from O'Donnell's cross and the latter stung the palms of Woodman from 22 yards.
Substitute Brophy and O'Donnell were denied by penalty-box blocks but Aberdeen eased the pressure before Christie came close from the rebound of his own free-kick and the game drifted into extra-time.
Killie took the lead after a long, high ball out of defence set up a counter-attack. Logan failed to deal with the bouncing ball and Brophy knocked him off it before squaring for O'Donnell to slot home.
The lead only lasted seven minutes before Kirk Broadfoot was adjudged to have pulled back substitute Stevie May inside the box. McLean sent Jamie MacDonald the wrong way before smashing the crossbar from 25 yards moments later.
Brophy headed home from a free-kick but the offside flag was raised and McLean continued his one-man mission to win the tie with a great piece of skill before shooting inches wide.
MacDonald tipped away Dons sub Chidi Nwakali's volley from distance to set up the shoot-out.
Woodman quickly emerged as the hero and Niall McGinn could even afford to hit the bar for Aberdeen, who did not need a fifth go.