Juergen Klopp accused referee Paul Tierney of having something "against" Liverpool after their thrilling 4-3 Premier League win over Tottenham Hotspur on Sunday.
Liverpool led 3-0 after 15 minutes but were pegged back to 3-3 when Richarlison headed past Alisson in stoppage time, with Klopp protesting a free-kick awarded to Tottenham in the build-up to the equalizer.
Diogo Jota then scored Liverpool's winner a minute later and Klopp confronted the fourth official before racing down the touchline to celebrate - for which he was shown a yellow card by Tierney.
Klopp has criticized Tierney in the past, saying he should have shown Spurs striker Harry Kane a red card for a dangerous tackle in a meeting between the sides in 2021, and on Sunday the German manager said Liverpool have "history" with the referee.
"I really don't know what he has against us," Klopp told Sky Sports. "He has said there is no problems but that cannot be true.
"How he looks at me, I don't understand it ... My celebration was unnecessary, which is fair, but what he said to me when he gave me the yellow card is not OK."
Klopp did not provide further details on the incident.
Referee's body PGMOL said they were aware of Klopp's comments, adding: "Match officials in the Premier League are recorded in all games via a communications system.
"Having fully reviewed the audio of referee Paul Tierney from today's fixture, we can confirm he acted in a professional manner throughout, including when issuing the caution to the Liverpool manager so, therefore, we strongly refute any suggestion that Tierney's actions were improper."
Klopp has been punished for comments about referees in the past. He was fined 45,000 pounds ($56,502) by the FA in 2019 for remarks about Kevin Friend.