Fuming Dundee boss James McPake claims Bobby Madden defended the decision to only yellow card Jon McLaughlin by saying the penalty "was missed anyway".
McPake was caught up in a touchline spat and shown a red card after the full-time whistle after the Rangers stopper was booked following the penalty box trip on Paul McMullan.
Jason Cummings would see the spot-kick saved by McLaughlin after he remained on the park.
McPake was adamant that the goalkeeper should have been given his marching orders, with the rule book stating the goalkeeper had to make a "genuine attempt for the ball" to remain on the pitch.
He claims the man in the middle rubbished his protests because misfiring Cummings missed the key penalty.
When asked how he would describe Madden following the altercation, the Dundee gaffer said: "Unapproachable.
"He said I'll not speak to you about it, and that he can't talk about an incident.
"Then you get the 'you missed the penalty anyway' shout, which; we know that. I was standing there, I watched it.
"Jason Cummings was excellent when he came on. I was worried about putting him on.
"All the rumours that it has been a faked illness, but that boy has had Covid twice and wasn't well through the week.
"I thought he was great when he came on and Paul McMullan caused them all sorts of problems through the middle. "
