Amorim’s biggest problem is that there are multiple issues to address. Some directly relate to personnel and others have resurfaced around players being able to carry out his tactics.
Onana’s performance in goal only underlined why United have been looking at a deal for Belgian goalkeeper Senne Lammens.
The Cameroon international should have done better for both Grimsby goals and exhibited the same vulnerability in dealing with crosses that underscored Altay Bayindir’s performances against Arsenal and Fulham.
“I don’t know what Onana is doing,” said former Manchester United forward Dion Dublin on BBC Radio 5 Live.
“For the second goal there is nothing at all, just a half-hearted attempt. I would be absolutely livid with my keeper doing that. I would expect to get smashed out of the way if my keeper is coming for a cross. But there was nothing at all.”
Former Blackburn and Celtic striker Chris Sutton added: “Bayindir looks a bag of nerves from crosses and Onana had his opportunity tonight and there’s lapses of concentration.
“I don’t know if he thought he could rock up here tonight and it would be a breeze, but it was anything but. How can Ruben Amorim have faith in Onana after that performance?
“What an embarrassment for Manchester United. Where does Ruben Amorim go from here? The perception of him now. I don’t think he gets over this.
“If I was Ruben Amorim tonight there is not a prayer that I would have made eight changes. I would have played my strongest team, try to put the game to bed and then make changes.
“That was an error from him in my book. He will struggle to come back from this. The pressure this season is well and truly on now. If I’m him, I am officially worried.”
On Sky Sports, former United defender Phil Jones and ex-Crystal Palace winger Jobi McAnuff criticised United’s approach.
“How many times was the spare man Matthijs de Ligt in the build-up? With the greatest respect to him, you should have an attacking player joining in and getting into the box,” said McAnuff.
“It just seems crazy that he [Amorim] is wedded to this formation at all costs, in any circumstances in a match that he is almost forcing people into positions no matter the state of the game. It is baffling that there is no flex at all.”
Jones added: “When he [Amorim] changed and put Mason Mount in that position they still went with a back five. They were building with a back five against Grimsby who were sitting on the edge of their own box.
“[But] if he changes now it will be seen as a sign of weakness for sure.”
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