When Manuel Pellegrini became Manchester City's manager in the summer, he arrived with a reputation for being a smooth operator, unflappable and calm under pressure.
Apart from getting a little irked by the odd Jose Mourinho jibe, the 60-year-old had maintained that image this season.
Then came Tuesday night when the Chilean lost his cool and the plot ranting about the influence of Swedish referee Jonas Eriksson after Barcelona defeated City 2-0 at the Etihad Stadium in the first leg of their last 16 Champions League tie.
Pellegrini didn't just question the integrity of the official, he insulted the footballing prowess of Eriksson's home country as well.
It was an unfair and unacceptable attack and one that should land him in serious trouble with UEFA.
The moody Blue claimed Eriksson was "not impartial to both teams" stating "the referee decided the game."
"He was on Barcelona's side from the beginning until the end," added Pellegrini, choosing to ignore his failings and those of his team.
The City boss was fuming that, with the match scoreless in the 54th minute, a foul was not given on his player Jesus Navas seconds before a penalty was awarded to Lionel Messi, who he felt was fouled outside the box by Martin Demichelis. The City defender was red carded after tripping Messi, who slotted home from the spot to break the deadlock.
Pellegrini said: "The more important mistake is the foul against Navas, and secondly the penalty.
"The first foul was outside the box. Before the penalty Barcelona did not have chances and we were preparing the way to score."
With Barcelona controlling the tempo, suggesting City were "preparing the way to score" was almost as ludicrous as what Pellegrini said next.
He declared that "it was not a good idea to put a referee from Sweden in charge of such an important match, and a referee who made an important mistake against Barcelona in a previous match. Today he arranged it."
Those inflammatory comments were in reference to Eriksson taking charge of Barcelona's Champions League quarter-final against AC Milan in 2012 when he failed to award a penalty despite strong appeals.
Looking at each point in turn, I didn't think Navas was fouled. At most it was a 50/50 call.
Regarding the penalty, thanks to the benefit of replays, a free-kick seemed more appropriate though former ref Graham Poll says that while the first contact was made outside the box, it carried on inside and therefore a spot-kick was the correct decision.
Open to discussion then. No debate surrounding the sending off however.
Having a dig at placing a Swede in charge of such a big game was a low blow.
Eriksson, a millionaire apparently, has been an international referee since 2002 so he has plenty of experience.
Pellegrini's verbal assault brought back memories of Mourinho when he was Chelsea boss first time around savaging Swedish whistler Anders Frisk after a game with Barca.
Frisk received death threats and was forced to quit.
We hope Pellegrini's words – which entered dangerous territory – don't provoke a repeat.
Manuel likes to see himself as the good guy in comparison to 'bad boy' Mourinho, who took over from the Chilean at Real Madrid and did what Pellegrini could not... win La Liga and this despite the South American having £210 million worth of signings handed to him early on in the shape of Cristiano Ronaldo, Xabi Alonso, Kaka and Karim Benzema.
It was Barca, superior to they are now, who proved too strong for Pellegrini then too.
While Mourinho doesn't try to hide his disagreeable characteristics, Pellegrini's mask slipped on Tuesday night. Wolf in sheep's clothing springs to mind.
Of course he was frustrated at seeing City's Champions League and trophy quadruple dreams fade but his reaction was way over the top.
Imagine what he'd have said had Eriksson made a howler like Howard Webb during Arsenal's FA Cup win over Liverpool at the weekend!
Funny how Pellegrini didn't mention that Barcelona could have been given a penalty when the ball hit Gael Clichy's arm and that the Catalan outfit had a goal chalked out for offside when it should have stood.
The Chilean didn't cane himself either for leaving more reliable options on the bench and picking the error-prone Demichelis in defence or go on about his conservative team selection ignoring the type of adventurous approach which had served the team so well in the Premier League.
It didn't do Bayern Munich any harm when they faced Barca in the Champions League last year.
Ultimately on City's big night, Pellegrini fluffed his lines and the players failed to live up to the billing they gave themselves against a Barcelona side, who, while good enough, were far from delivering the greatness of the recent past.
That was not the referee's fault. Nor was it that the Blues had to play Barcelona in the first place.
We wondered if Pellegrini's miscalculations against Bayern of what was required to top their group and avoid the big hitters would come back to haunt City. Now we know.
Manchester City only have themselves to blame for their impending European exit, not a Swedish referee.