Wayne Rooney has admitted that he is “worried” about Manchester United, despite them clinching a narrow win over Newcastle on Boxing Day. A depleted United side won 1-0 at Old Trafford, but Rooney has called on the club to sign players in the January transfer window, or risk sliding down the Premier League table.

United manager Ruben Amorim was without Bruno Fernandes, Harry Maguire and Matthijs de Ligt for the game, while Mason Mount also went off injured. Meanwhile, Bryan Mbeumo, Amad Diallo and Noussair Mazraoui are away at the Africa Cup of Nations.

Amorim switched to a back four and was rewarded when Patrick Dorgu scored his first goal for the club. The United boss also used academy graduates Jack Fletcher and Tyler Fredricson off the substitutes’ bench, which also contained fellow youngsters Tyler Fletcher, Shea Lacey and Bendito Mantato.

United legend Rooney was happy to see his former side hang on and claim three points, which left them sixth in the Premier League, and academy players given a chance to impress, but couldn’t hide his overall feelings. “I was worried when I saw the performance, if I’m being honest,” Rooney said on Match of the Day.

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“The manager changed the formation and he went with a back four, which a lot of people have been asking for. I know they didn’t concede a goal but they didn’t really look comfortable and Newcastle put them under pressure, especially in the second half.

“And when I look at the squad and the bench, what they’ve got there, they really need players in to try and help them to challenge and get into the top four.

“It’s great to see the young players on the bench and getting that opportunity, but it needs to be at the right time as well. It’s not sustainable at all. They need players in. They’ve obviously lost some important players and Bruno is a big loss.

“They had 33 per cent possession in the Newcastle game – and I know when those fans go to Old Trafford they want to see the team with the ball, they want to see them entertaining, getting crosses into the box and getting shots off. It was a poor performance, but they found a way to win.”

United are understood to be chasing a midfielder in the January transfer window, with Everton’s James Garner and Atletico Madrid’s Conor Gallagher among the targets. The club have previously considered Crystal Palace’s Adam Wharton and Brighton’s Carlos Baleba after spending £200million in the summer transfer window to bolster their attack.

Amorim has already ruled out panic-buying in January after losing captain Fernandes to injury. “What we cannot do is to reach January and try to do everything in urgency and make mistakes and then [it’s] ‘here we go again’ with a lot of mistakes,” Amorim said last week.

“I’m not going to get [together] with [club chiefs] Jason [Wilcox] and Omar [Berrada] and say: ‘We need a lot of players.’ Because we have a plan.

“If we have to suffer, the club comes first. Of course, we are in a moment where we need points but we need to find solutions and we are going to continue with our plan. You can feel in this moment that we are going to struggle, but we will see. We have to deal with it.”

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