Rangers suffered a humiliating Scottish Cup exit at the hands of Queen's Park after James Tavernier missed a stoppage-time penalty in Sunday's shock 1-0 defeat against the second tier minnows.
Philippe Clement's side paid the price for a dismal display in the fifth round tie at Ibrox, with Seb Drozd's second-half strike putting Queen's Park ahead before Calum Ferrie saved Tavernier’s spot-kick.
One of the biggest upsets in Scottish Cup history could the final straw for the Rangers board as they ponder the future of the beleaguered Clement.
Thirteen points behind Celtic in the Scottish Premiership, beaten by their Old Firm rivals in the Scottish League Cup final and now out of the Scottish Cup, Clement's hopes of avoiding the sack appear bleaker than ever after the lowest moment in a dismal season.
Rangers are through to the Europa League last 16, but whether Clement will still be in charge by the time they return to European action remains to be seen.
Adding to the ignominy for Rangers, it is the first time Queen's Park have reached the Scottish Cup quarterfinals since 1928.
"The first half, not a high enough tempo. Because of that, we didn't create enough. I was not happy at halftime," Clement said.
"Second half, there was more chances but too much in a rush. One chance against, and they get the goal.
"We had more efforts on target today than we have had all season, but we didn't manage to score, not even with a penalty.
"We lacked quality in the last decision-making and last action. Maybe the team wanted to react too much."
Ferrie was the underdogs' hero, saving from Mohamed Diomande, Vaclav Cerny and Nedim Bajrami in the first half.
Callum Davidson's Championship side kept Rangers at bay with a gritty display before pouncing in the 69th minute.
Drozd had been on the pitch less than three minutes as a substitute when the former Millwall youth academy prospect latched on to a corner from Louis Longridge, eluded Jefte and fired past Rangers keeper Liam Kelly from 12 yards
With just seconds left in stoppage-time, Rangers thought they had earned a lifeline when William Tizzard conceded a penalty with his challenge on Cyriel Dessers.
But Tavernier's spot-kick was superbly saved by Ferrie, who quickly composed himself to tip over Robin Propper's header from the resulting corner.
The final whistle went moments later as Rangers slumped to the turf while Queen's Park players danced in delight all around them.
"The boys were fantastic today. The goal gave us something to hang on to," Davidson said.
"No one expected that. We had four fit defenders. I woke up at 1.30am and hoping no one was ill. We didn't have a back-up plan."
"All credit to the group. It doesn't come from individuals, it comes from the group."