Ruben Amorim is fighting to retain the confidence of his Manchester United players following their derby debacle.

United's 3-0 defeat at Manchester City piled the pressure on Amorim, with the Portuguese head coach fighting to save his job. It is understood some of United's senior players have been left frustrated and confused by Amorim's refusal to change his tactics and system.

Amorim's rigid 3-4-3 formation and his refusal to adapt to any other set-up is said to have caused huge concern among key members of the squad. Some United players are said to feel Amorim is undermining them by repeatedly asking them to fit into a system they are not equipped to play.

Pressure is mounting on Amorim to turn United around after their poor start to the season, which has seen them take four points from as many games. United sources insist "nothing has changed" in terms of their support for Amorim and that he retains the full backing of the club hierarchy.

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But United supporters were left stunned by their side's meek capitulation at the Etihad Stadium, with many feeling they got away lightly by only losing 3-0.

United have won just one game this season – needing a 97th-minute penalty to beat newly-promoted Burnley – and crashed out of the EFL Cup to League Two Grimsby. After United finished 15th last season, their lowest place for half a century, Amorim needed a strong start to the new season but has failed miserably.

He has won just eight of his 31 Premier League games in charge, while United's four point haul is their worst start to a season since 1992. Amorim has been backed in the transfer market this summer, with United spending almost £236million on strengthening his squad.

But the new additions of Bryan Mbeumo, Matheus Cunha, Benjamin Sesko and Senne Lammens have so far not had the expected impact, while Amorim is refusing to compromise on his style of play and formation.

United legend Wayne Rooney claimed the team have got worse since Amorim replaced the Erik ten Hag 10 months ago. “It's hard to see how it continues,” Rooney told BBC Sport. “I don’t think anyone can understand and comprehend what's going on. Frankly, it's not good enough.

"I want to be as supportive and positive as I can be on the manager and the players. But it's very difficult to sit here and say we're seeing progression and at least we're seeing things that will get results in the near future.

"When Ten Hag got sacked and Ruben came in, we were hearing how they're going to play and how it was going to change. I think if the manager is honest with himself, it's got worse."

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