Leicester City boss Sven Goran Eriksson was upset with on-loan Chelsea defender Jeffrey Bruma after their 3-3 draw with Middlesbrough.
Bruma saw red 13 minutes from time. He picked up a second booking for dissent following the controversial penalty decision when a Julio Arca shot hit the Leicester man as he tried to turn his back on the piledriver.
Eriksson admitted his side had to learn to hold their tongues regardless of their frustrations.
"Players should not talk to the referee and should not discuss with him any decisions," he said. "I will talk to the referee when he comes off.
"If players argue with the referee they will get booked. Some of my players need to be reminded of that."
