Steven Gerrard admitted he was running out of ideas to tackle Rangers' discipline problems after Allan McGregor's "moment of madness" earned a late red card against Hibernian.
The 37-year-old goalkeeper kicked out at Marc McNulty in the 89th minute of Rangers' 1-0 win at Ibrox – moments after making a brilliant close-range stop from Florian Kamberi.
Rangers had to see out a dramatic finale with Ross McCrorie in goal, having used all three substitutes.
McCrorie did not have any chance to show whether he shares any of the goalkeeping talent of his twin brother and Rangers team-mate Robby, who is on loan at Morton.
But McGregor's acrobatic kick at McNulty following a kick-out from his hands will see him miss the final two games of the season, including next weekend's visit of Celtic, as well as the first game of next term.
The Rangers manager said: "I can't defend it. He pulls a world-class save off to get us three important points and then he has a moment of madness where he loses control.
"It's frustrating because we will miss our number-one keeper now and that will start with a very important game next week.
"It is frustrating, I should be going away thinking 'we didn't play well but it's three good points, the run goes on'. But I'm not, I'm going away frustrated because I'm going to miss my keeper, who has been magnificent for me throughout the season."
The red card was Rangers' 12th of the season in all competitions. Alfredo Morelos' first of five dismissals was later rescinded but both McGregor and Ryan Kent have had retrospective bans after red-card offences were missed on the day by match officials.
Gerrard – whose team triumphed courtesy of Jermain Defoe's goal late in the first half – said: "I'm open to advice if anyone wants to give me any because I'm sure the players are sick of listening to me talking about discipline. It's nine (league) red cards. That's crazy.
"Our discipline problem is probably the reason why we are not talking about success and are talking about falling short, if you analyse it properly. This game is hard enough with 11. You need to be disciplined and keep your best players on the pitch.
"The players are not helping themselves but I'm running out of things to do to address it. I don't want to be one of these managers who takes money out of the players' pockets, they've got families, it's not the type of man I am. But they are leaving me with no other option."
Hibernian suffered their first defeat in 11 Ladbrokes Premiership games under Paul Heckingbottom and saw their slim hopes of a top-four finish and Europa League place disappear.
Heckingbottom said: "It's disappointing but the bigger picture is I'm really pleased with the progression and what the players have been doing. And I think they should be as well.
"What I don't want to think is it's a failure. We have come a long way and I'm pleased with that."
