Pep Guardiola has been accused of trying to pressure referees and opposition players in a scathing attack on the "extremely unpleasant" Manchester City manager.
Porto coach Sergio Conceicao has taken aim at Guardiola as the fall-out from Wednesday's fractious Champions League match at the Etihad Stadium continued.
Guardiola and Conceicao had exchanged words either side of half-time of a heated encounter and in the closing minutes of the game the City manager and Brazil midfielder Fernandinho became embroiled in a spat with the Porto coach and his bench.
Fernandinho had taken exception to the Porto substitutes urging referee Andris Treimanis to book Raheem Sterling for perceived play-acting, even though their defender Pepe had been fortunate not to concede a second penalty of the night for fouling the England forward.
City had come from behind to beat the Portuguese champions 3-1 thanks to a controversial spot-kick from Sergio Aguero and goals from Ilkay Gundogan and Ferran Torres.
Porto were furious at the penalty award and felt it should have been ruled out for a foul by Gundogan on goalkeeper Agustin Marchesin.
Conceicao cut an animated figure on the touchline throughout the night, when City were left exasperated by some of the theatrics of Porto's players and decisions of Treimanis, who booked five home players.
Yet Conceicao insisted Porto had been "angels" compared to the behaviour exhibited by Guardiola and the City bench and launched a stinging attack on the Catalan.
"I've got a lot to learn from Pep Guardiola, in the way he pressures referees, talks to opposition players and opposition dugout," the Porto coach told Portuguese media. "He's a fantastic example. I have to learn this. We were angels compared to the other dugout.
"He spoke about our country using ugly words. Guardiola's attitude was extremely unpleasant. The whole Manchester City dugout was because if anybody should have been complaining, it was the Porto bench, because we were extremely hard done by."