So it is not just Jose Mourinho who is losing his head in Manchester this season.
Pep Guardiola was supposed to bring a more measured approach to Manchester City — calmness rather than chaos, focus rather fury — but as his team left the field at the end of a 3-1 defeat against Chelsea at the Etihad Stadium, they did so with nine men, after the late dismissals of Sergio Aguero and Fernandinho.
The two red cards, one for a wild challenge by Aguero on David Luiz, the second for Fernandinho after he twice grabbed Cesc Fabregas by the throat before pushing the Chelsea midfielder into the crowd, will prove costly with Aguero facing a four-match suspension and Fernandinho set be banned for three games.
And Guardiola was no saint, either.
The Spanish coach’s constant bickering with fourth official Mike Dean and sarcastic applause of referee Anthony Taylor’s decisions — Guardiola punched the air in celebration at one point — was hardly the example to set for his players, who followed their manager’s lack of discipline to even greater measure on the pitch.
City simply lost their heads and lost their momentum, handing that to Chelsea, who must now be considered as favourites to regain the title after their eighth successive Premier League win.
Who would have thought that it would be a Chelsea team, with Diego Costa acting as peace-maker, who would keep their heads while all around them were losing theirs?
By the time Aguero and Fernandinho saw red in the final seconds of stoppage time, City had thrown away a one-goal lead with some calamitous defending to lose significant ground to Antonio Conte’s developing team in the title race.
Perhaps Chelsea’s comeback had prompted the red mist to rise among Guardiola’s players, with Fernandinho, in particular, forced to work overtime in his role as anchor between the porous back three and Guardiola’s attacking midfielders.
Aguero was also weighed down by frustration, having seen good opportunities missed on an afternoon when he was involved in a spiky, physical battle with David Luiz.
But City, for whom Kevin De Bruyne missed an open goal moments before Chelsea’s equaliser, undoubtedly lost their composure at the end of the game, and their failure to control their emotions could ultimately prove as damaging to their title hopes as their ongoing inability to defend properly.
Chelsea’s victory was not merely down to City’s shortcomings — far from it.
Antonio Conte’s team displayed incredible belief and resilience to overturn a deficit for the second successive game against a title rival, and they were the better team.
Where City have problems at the back and in goal, Chelsea are solid and consistent.
They also possess a defensive midfielder in N’Golo Kante who makes such a difference for his team with his work rate and reading of the game.
City simply do not have a player of Kante’s ability and, with a defence that has kept just two clean sheets in the Premier League all season, their inability to protect the likes of John Stones and Nicolas Otamendi with a midfield shield suggests they will struggle to win the title this season.
But while the melee at the end of the game will dominate the headlines, it is the events on the pitch before the late flashpoint that will be the greatest cause of concern for Guardiola. His team is worryingly unbalanced, and opponents are now visiting the Etihad Stadium without the fear that paralysed teams in the early weeks of the campaign.
This might have been City’s first home defeat under Guardiola, but they have now not won in the league at the Etihad since putting four past Bournemouth on Sept. 17, so it is anything but home sweet home.
David Silva continues to be arguably the best attacking midfielder in the league, with De Bruyne also capable of walking into any other team, but Aguero’s head is not where it should be; Stones and Otamendi are struggling at the back; and, in Claudio Bravo, Guardiola has made a clear mistake by going with the error-prone goalkeeper ahead of the exiled Joe Hart.
Tactically, Guardiola’s team remain an enigma.
The inverted full-backs from the early weeks of the season have been replaced by three at the back, with the attack-minded Jesus Navas and Leroy Sane offering nothing defensively against Chelsea.
And Fernandinho was increasingly struggling to plug the gaps, attempting to repel opponents on his own.
Ilkay Gundogan should have offered greater protection against Chelsea, but the German was neither attacker nor defender in one of his poorest performances to date in a City shirt.
Guardiola came to the Premier League for the challenge and the chance to win a domestic title in a third European league, but he is finding it much more difficult than he would have imagined.
Rival managers are relishing the opportunity to take him on and outthink him, while their players are also stepping up to the plate against City.
And as Guardiola and his players lost the plot, it betrayed a sense of annoyance within the team that everything is not going their way.
So just like Mourinho across town, Guardiola is now beginning to feel the heat.