Amorim's departure came in the wake of scathing public criticism he aimed at the Manchester United hierarchy last weekend, bringing an abrupt end to a tenure that was consistently overshadowed by instability.

United's latest managerial change continues a long-running pattern of upheaval that has defined the club since Sir Alex Ferguson retired in 2013, shortly after securing the club's most recent English league title.

Fletcher has temporarily stepped up from his role as the club's under-18s coach and will take charge of the first team for Wednesday's Premier League fixture away to Burnley.

The former Scotland international confirmed that he has not been able to speak to Amorim since assuming the caretaker position but did reveal that he consulted Ferguson before accepting the role. Ferguson, who remains a regular presence at United matches, is understood to have offered his support.

The appointment makes Fletcher the club's sixth caretaker manager since Ferguson's retirement, underlining the lack of long-term stability in the dugout over the past decade. While Fletcher's role is strictly interim, speculation has already begun over who could replace him.

"I have (spoken to him). I don't like to make any major decisions or things without speaking to Sir Alex and that's something I've done since I've been at the club and since I've left the club in everything I do," Fletcher told reporters on Tuesday.

"I've got a really good relationship with Sir Alex, so he's probably the first person that phoned actually, so I wanted to speak to him first and ultimately to get his blessing, to be perfectly honest with you. I think he deserves that respect.

"I wanted to run it by him, what he thought, and he was supportive of it and he echoed my thoughts which I've always said - it's your job to do the best for Manchester United.

"When you're an employee of the club, it's your job to do your best for Manchester United and it's amazing when he says something that I try and live and believe every day, so it was comforting for me for him to say that."

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