The Red Devils were held to a frustrating goalless draw with Crystal Palace at Old Trafford on Saturday afternoon to lose more ground on their rivals.
Manchester United are already 14 points adrift of current leaders Manchester City, while second-placed Liverpool FC are 12 points ahead of Jose Mourinho’s men.
On a positive note, Chelsea FC’s 3-1 loss to Tottenham Hotspur meant Manchester United’s stalemate saw the Red Devils move a point closer to the west London side, who occupy fourth spot.
The 20-time English champions have been linked with a number of potential signings in the January transfer window, including AS Roma midfielder Lorenzo Pellegrini and Inter Milan defender Milan Skriniar.
However, former Liverpool FC captain Redknapp believes Manchester United will struggle to attract new additions given their uninspiring performances.
“Did anyone seriously expect Manchester United to put Crystal Palace to the sword after Jose Mourinho’s criticism of his players?” Redknapp told the Daily Mail.
“Mourinho said before this game that some of his young stars lacked character. One of those was Jesse Lingard, who last week showed immense fight from the bench to haul England back into the game against Croatia.
“Calling out your players publicly is a sure-fire way of losing them. Mourinho has made no secret of his desire to improve his squad. United are of course still a huge club but would the best players really want to go to Old Trafford in January with this manager in charge?
“His marquee signings — Paul Pogba, Romelu Lukaku and Alexis Sanchez — are struggling to hit the heights, the style of football is negative and the fans are growing increasingly frustrated.”
Manchester United signed Shakhtar Donetsk midfielder Fred, FC Porto defender Diogo Dalot and Stoke goalkeeper Lee Grant in the summer transfer window.
The Red Devils have failed to close the gap on defending Premier League champions Manchester City, and in fact, look to have lost ground on Pep Guardiola’s side.
Manchester United will take on Young Boys in the Champions League on Tuesday night after a 2-1 win over Juventus last time out.
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