According to the Daily Mail, Manchester United still supports Amorin, but as the team's recent performance continues to decline, players are losing confidence in his system.
After a 0-3 defeat at Manchester City on Sunday, Amorin insisted he would rather be fired than change his football philosophy.
Amorin still has support from Sir Ratcliff and club executives, but he is in danger of losing some of the locker room support due to his refusal to compromise.
It is understood that some players have never adapted to the 3-4-2-1 formation introduced by Amorin.
Manchester United hopes to give Amorin a complete pre-season preparation period to run in with the team and invest £236 million to introduce new players to adapt to their system, which will improve the results after the club experienced its worst season in more than half a century last season.
However, Manchester United scored its worst season start in 33 years, scoring just four points in the first four Premier League games and being eliminated by English League Two underdog Greensby in the League Cup. Nearly 11 months after Amorin took over, the players are still trying to adapt to his style, and even Captain B Fee, one of his most determined allies, is dissatisfied with the midfield role being placed in the retreat.
Manchester United sources said it was wrong to say that Amorin had lost support from the locker room and insisted that he still had support from some players in the team.