Returning goalkeeper Lionel Letizi took the flak as Inverness Caledonian Thistle defeated Rangers for the first time thanks to a Graham Bayne goal.
Many Rangers fans blamed Lionel Letizi for the goal
Thomas Buffel and Filip Sebo had come close as Rangers dominated possession, but they lacked penetration against an organised Inverness defence.
Rangers manager Paul Le Guen had dropped in-form keeper Allan McGregor to make way for fit-again Letizi.
But the Frenchman spilled a Craig Dargo effort to allow Bayne to score.
And Rangers fans made their displeasure known not only at the decision to drop Scottish Premier League player of the month McGregor but a result that leaves their side 10 points adrift of leaders Celtic.
Sebo, who netted the winner in their last game against Aberdeen, had also been drafted into the top team in place of the injured Libor Sionko.
Rangers dominated possession in the opening stages and had Inverness under pressure when a Buffel corner broke to Filip Sebo and he drilled across the face of goal and wide.
Buffel flighted a cross on to the head of Charlie Adam but his effort flashed over the crossbar from just inside the area.
Letizi was then called into action for the first time to block a John Rankin shot.
But he could not smother the ball and the Frenchman was fortunate to see Roy McBain's rebound sail over.
Caley Thistle won thanks to Graham Bayne's goal
Brown was called upon to keep the scoreline level in the other goal when he just managed to hold a thunderous Phil Bardsley strike on the line.
Rangers should have taken the lead when Adam fed Buffel and he turned in the box before unleashing the shot, but Brown had raced off his line to block.
Buffel was then denied in front of a gaping net when Richard Hastings bravely threw his body in front of goal to block.
Ian Black, who had started in the Inverness midfield ahead of Richie Hart, had a 20-yard effort held by Letizi.
Buffel fired just over from just six yards following Rangers' seventh corner of the match.
Rangers were pressing forward, but Caley Thistle broke clear to open the scoring.
A Craig Dargo shot was spilled by Letizi, who failed to recover in time to prevent Bayne bundling the home the rebound from six yards.
Smith fired across goal and just wide of the far post as Rangers responded.
And substitute Nacho Novo had a penalty claim denied late on.
Rangers: Letizi, Bardsley, Rodriguez (Novo 73), Papac, Smith, Hemdani, Ferguson, Adam, Buffel, Prso (Kris Boyd 59), Sebo.
Subs Not Used: McGregor, Rae, Svensson, Hutton, N'Diaye.
Booked: Bardsley, Kris Boyd.
Inverness CT: Brown, Tokely, Dods, Munro, Hastings, Wilson (Hart 87), Black, McBain, Rankin, Dargo (Duncan 83), Bayne.
Subs Not Used: Fraser, McCaffrey, Wyness, Sutherland, McAllister.
Booked: Black, Dargo.
Goal: Bayne 71.
Ref: I Brines