has wasted no time in making it clear to players that they won't be getting their own way under his rule. The Portuguese head coach's decision to dismiss was widely acknowledged as necessary among many supporters yet proved unpopular in other corners of the fanbase.
The latter sentiment will have extended into the United dressing room due to the strong rapport Van Nistelrooy built with his players during his four-match reign as interim manager.
The Dutchman's surprise summer return would have been just as welcome behind the scenes as it was amongst fans, but it was significantly shorter than expected.
After United's 3-0 win against Leicester City on Sunday, his third in four games in caretaker charge, reports claimed the players wanted Van Nistelrooy to stay put.
Given how effectively he communicated during and after Erik ten Hag's tenure as boss, he is said to have been viewed as their 'connector' to the coaching staff.
There was reportedly a swell of support to keep Van Nistelrooy on board in some capacity, especially amongst leadership figures in the squad.
On Sunday, United goalkeeper Andre Onana even publicly pleaded for Amorim to retain the 48-year-old's services once he took the reins the following day.
"100 per cent," Onana responded when asked whether the United players wanted Van Nistelrooy to remain at Old Trafford.
"He's a very good guy, a very good coach. Since he's here, he's helping us a lot. He has so much experience and he advises us a lot. He's doing amazing since he's here, you know.
"Obviously, we have him a few days as a head coach. He's different, but he's doing amazing. It's fantastic what he's doing, and the players are happy.
"But at the end of the day, it's not something we can decide. The club make the decision, and we have to accept it.
"But this has to be between him and the club because at the end of the day, they are the ones who have to sit at the table and decide what is best for the club."
Indeed, the final decision was with Amorim, who opted to snub his new players' sentiment and parted ways with Van Nistelrooy on his first day at Carrington.
The 39-year-old is expected to bring five members of his coaching staff with him from Sporting, as well as an analyst.
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