The Rangers Supporters' Trust have warned there could be further fans' demonstrations if results and displays do not improve.
Some supporters criticised Ibrox chairman David Murray and called for manager Alex McLeish to leave in the wake of the Tennent's Scottish Cup fourth-round defeat by Hibernian.
The result leaves the Light Blues without a realistic chance of silverware this season, despite a place in the last 16 of the Champions League.
But Trust spokesman Stephen Smith believes Saturday's outburst could be repeated unless an improvement is made.
He said: "Regrettably, the protests will continue and will come after the next bad performance or result. There is just such a malaise there now.
"The Trust doesn't organise these protests, but you can understand why they are happening because supporters need clarity over how the club is going to turn itself around.
"If Celtic batter Rangers on Sunday or bad losses are suffered to Villarreal or Hibs, the same will happen."
He added: "There is a lot of discontent and it's time for the chairman to say what the situation is for the rest of the season.
"We were led to believe we would get three players and they didn't arrive.
"What has happened to the big investment that was promised as well?"
