Ruben Amorim admitted Manchester United need a “shock” and are being dragged into a relegation fight after their 2-0 defeat by Newcastle at Old Trafford on Monday night.

It leaves United in 14th place on 22 points at the halfway stage of the Premier League season, seven above the drop zone. The defeat came after first-half goals from Alexander Isak and Joelinton and is United’s fourth consecutive loss in all competitions and the first time three consecutive home league matches have been lost since 1978-79.

“Our club needs a shock and we have to understand that,” Amorim said. “It is also why I speak of relegation. That is really clear [the possibility] and we have to fight. It is a really difficult moment, one of the more difficult moments in the history of Manchester United and we have to address it with honesty and to be clear with that, we have to fight [in] the next game.”

That next game is the difficult trip to Liverpool, the league leaders, on Sunday. Amorim has endured five defeats in his first eight league matches, the poorest of any United manager for 103 years, but he will have little money to strengthen next month unless major sales are made.

“We don’t have that possibility in January if we don’t take [sell] some players,” Amorim said. “You know the situation better than me. It is not that I am arriving here and can spend money changing the team.”

The squad that Amorim inherited was not built for his 3-4-3 formation. The head coach was asked why he did not wait until the close season to implement it. “When you have a change of coach, especially in this type of club, it is because they were not winning,” he said. “They play in the system they were bought for and were losing. So I am going to change to that system? This team was already in trouble.”

Marcus Rashford was reinstated to the match squad but remained an unused substitute. Amorim was asked why. “I think about the team, you a lot about Marcus. I just want to win the game,” he said.