Former Liverpool striker Stan Collymore has described Jurgen Klopp as 'spiteful and unprofessional' for the manager's conduct during his post-match media duties.
The German coach took issue with a Sky Sports reporter over referee Craig Pawson's penalty decision in Sunday's Merseyside derby.
The match official pointed to the spot when Dejan Lovren was deemed to have nudged Dominic Calvert-Lewin in the box, which resulted in the Everton forward hitting the deck.
Wayne Rooney converted the penalty to cancel out Mohamed Salah's first-half strike and earn the Toffees a 1-1 draw at Anfield.
In his column for The Mirror, Collymore wrote that the penalty should not have been given, but Klopp's reaction was unacceptable.
"[The Liverpool manager] lost face by having a go at Sky Sports' Patrick Davidson and telling him he 'only wanted to talk to people who have a little bit of understanding about football' after the reporter had given his opinion that it was a 'soft penalty'," wrote Collymore.
"What Klopp didn't realise was that the pundits back in the studio, with something like 600 caps and five Champions Leagues titles between them, had agreed with their colleague. It was cowardice on Klopp's part and he should not have done it.
"When managers vent at like that they are basically taking their frustrations about an official, their players, opposition players or managers out on a convenient target.
"And in this instance there was an element of the mask dropping and the side of Klopp we rarely see behind that big laugh and smile revealing itself. He came across as spiteful and completely unprofessional."
The result means that Liverpool sit fourth in the Premier League table and Everton 10th.