Mark Hughes believes Simon Mignolet should have been dismissed for bringing down Mame Biram Diouf early in Stoke City's 3-0 home loss to Liverpool.
Mignolet was only shown a yellow card for tripping Diouf outside the area just as the attacker appeared set to restore parity in the 39th minute at bet365 Stadium.
Liverpool went on to add two further goals to Sadio Mane's opener through substitute Mohamed Salah, consigning the hosts to consecutive Premier League defeats.
Hughes, who also felt the ball had gone out of play in the lead-up to Mane's goal, felt aggrieved after the match.