The inquest will begin on the Manchester United training ground in the coming days after Ole Gunnar Solskjaer's side were shocked 2-1 in the Champions League by European minnows Istanbul Başakşehir.
It looked like United had turned a corner in recent weeks after they beat the likes of PSG and RB Leipzig.
But they have subsequently lost to Arsenal and Istanbul, and the pressure is now once again mounting on Solskjaer, with Saturday's trip to Everton looking like a must-win one if he is to keep his job.
What was particularly galling about Wednesday's loss was how badly United defended, with the first goal they conceded especially poor.
A short corner in United's favour was cleared to Demba Ba, who had no defenders anywhere near him, and the former Chelsea man had all the time in the world to race through and finish past Dean Henderson.
Former Arsenal centre-back Martin Keown was watching this as a co-commentator for BT Sport, and could clearly not believe what he was seeing.
As Ba received the ball and it became apparent he was on-side and with nobody near him, a baffled Keown can be heard whispering: "Jesus".
Once Ba converts Keown then laid into the defending, saying: "It's almost comical, isn't it?
“How on Earth is Demba Ba stood all alone? Matic is just switched off, Tuanzebe can’t get back and he tucks it away beautifully.
“It’s embarrassing though, the organisation for that goal, when the ball is at the other end of the pitch, but nobody is anywhere near Demba Ba."
Keown was almost just as unimpressed with the second goal, with Juan Mata giving away possession and Edin Visca left in acres of space to finish.
"Again it's sloppy play by Manchester United, and it's a breakaway goal to make it 2-0," he said.
Unless the defence improves considerably over the coming days the likes of Dominic Calvert-Lewin and James Rodriguez could have a field day at Goodison Park on Saturday, and Solskjaer has an awful lot of thinking to do before then.
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