Manchester City boss Pep Guardiola hugged the ref after being shown a yellow card in victory over Borussia Dortmund.
After a dramatic finish to their Champions League encounter, Guardiola began remonstrating with Italian referee Daniel Orsato at full-time as Phil Foden also tried to argue his point.
The City boss continued to angrily gesticulate towards the match official as he walked away and appeared to tell him to 'f*** off'.
Orsato booked Guardiola, who comically hugged the referee as he tried to get him back onside. The pair then had a much calmer exchange as they tried to explain their viewpoints.
City were frustrated by their German opponents for much of the night at the Etihad Stadium and trailed soon after half-time as Jude Bellingham glanced a header past a helpless Ederson.
But two incredible goals in the final 10 minutes - first a bullet strike from John Stones and then a remarkable acrobatic finish from Erling Haaland - turned the game around in City's favour.