Pep Guardiola approached the referee with a parting shot: "Thank you so much."
The Manchester City manager's comment in earshot of the onfield camera was dripping with disdain.
Regardless of later assurances to the media — "it was not sarcastic" — there was no doubting his irritation toward Michael Oliver after the 3-1 loss to Liverpool on Sunday.
Refereeing has been in Guardiola's sights, especially after the introduction of VAR. And particularly after this third loss in 12 matches of the title defense left City nine points behind Premier League leader Liverpool in fourth place.
It could all be a smokescreen for a tilt at a third successive title fading, with 26 games still to play and Liverpool well placed to end a three-decade drought by sitting eight points ahead of Leicester and Chelsea.
What got Guardiola so worked up? City not being awarded a penalty just before Liverpool raced up the other end and scored.
"Ask to Mike Riley and the big bosses about that," Guardiola said, citing the league's head of refereeing. "Don't ask me."
Premier League referees never appear on camera to explain decisions and the audio feed to the VAR is not public. So scattered explanations behind decisions only drip out of the world's richest soccer competition.
Just five minutes into the game, Trent Alexander-Arnold's outstretched right arm handled the ball but it was not deemed to be deliberate.
But City midfielder Bernardo Silva had already helped the ball on with his hand, appearing to be in contravention of the new laws of the game against the attacker.
With play continuing, Liverpool launched a counterattack that saw Sadio Mane charge down the left flank from inside his own half.
"It's their quality," Silva said. "You cannot give them much space."
A cross into the penalty area was cleared by Ilkay Gündogan directly to Fabinho who struck powerfully from distance in the sixth minute past Claudio Bravo, who was filling in for the injured Ederson.
City's makeshift defense was breached again in the 13th minute, again from a rapid move down the left.
When Andrew Robertson was set up by fellow fullback Alexander-Arnold to send a cross into the penalty area, Mohamed Salah got ahead of Fernandinho to head past Bravo.
"Trent's obviously done an unbelievable diagonal and I've just had a bit of space," Robertson said. "I've just seen Bobby (Firmino) and Mo (Salah) running into good spaces.
"I knew if I could put it in there, then one of them would hopefully get on the end of it. I'm delighted for Mo to get his head on it and put it in."
But far from being demoralized, City made the rest of the half uncomfortable for Liverpool.
Left back Angelino, on only his second Premier League start, saw a shot deflect off the post. And Sergio Aguero dragged a shot wide in a stadium where he has not scored now in eight appearances.
Any prospect of a comeback appeared to be extinguished six minutes into the second half when City was picked apart from another cross.
Mane got on the end of Jordan Henderson's delivery from the right, heading in at the back post.
On a frustrating trip across the northwest for City, Silva pulling one back in the 78th with a low strike was as good as it got.
"Always be positive and never give up, that's why we won back-to-back titles," Guardiola said. "We want to fight until the end. We dropped points for our faults. For other things we cannot control."