Ruben Amorim insists he won't compromise on his principles at Manchester United, despite admitting the club are in a relegation battle after five defeats in six Premier League games.

United are 14th at the halfway stage and a run of dismal results under Amorim has left them looking anxiously over their shoulders, with just a four-place and seven-point cushion to the relegation zone and a trip to Liverpool to come this weekend.

The upturn in results under Amorim has quickly come to an end and the players are looking lost in his 3-4-2-1 system, with the 2-0 defeat to Newcastle a third game in a row without finding the back of the net.

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Amorim enjoyed success at Sporting CP with his back-three system and he has stuck with it at Old Trafford, ditching the four-man defence that United had played under Erik ten Hag and trying to fit players into his new structure despite a lack of specialists.

The 39-year-old is well aware United's form has plunged them into an unexpected relegation battle, but he intends to stick with his three-man defence and said it was the only idea he had to bring success to Old Trafford.

"It’s like playing with three is more or less the same playing with four," he said. "We can change the characteristics with Amad on the wing, it could be a little bit different, we had some games that we press in 4-4-2, so I don’t see it that way. Of course, I didn’t choose the players specifically for that position, that I already knew.

"But I have to sell my idea, if I change all the time it will be even worse. But I understand they have a lot of difficulties because they spend two years playing one way and now playing another, with a lot of losses, is really tough on them and you can feel it during the games. Even when we try to score, was more from them than the organisation. You have to feel it. I have to sell my idea, I cannot find another one."

Amorim has said he needs results to sell that system to the players, but after a bright beginning his reign is now in danger of unravelling. Despite that, he has faith in his own methods and is prepared to back them to the hilt.

"If I change the system completely I don’t know if I’m here to win," he said. "You know? If I do that and continue to lose, it’s worse. You don’t know, I don’t know.

"I see the game in a different way, it doesn’t matter if you are three, four or five, if you know the basics, if you can train that idea, I see the game in this way, so I understand what you are saying but if I know for sure changing everything is going to get us near to win games I will do it."

Amorim also rejected the suggestion that he would have been better off waiting until the summer to fully implement his methods, pointing out that a squad signed to play 4-2-3-1 under Ten Hag had also struggled in that shape.

"When you have a change of coach, especially in this type of club, it’s because they are not winning and they played specifically in that system they were bought for and chose perfectly for that system," he said.

"In that moment, with the idea, with two years working in pre-season, they were losing, so are we going to change to that system that I don’t believe in to change to win games? It doesn’t make sense.

"So I can understand your ideas. For me, it’s more simple than that. If I think the players for right profile for each position it will be different but I have to start now in this moment because this team was already in problems. I have to teach what I know, that is my focus and I believe on that."