The Red Devils suffered a 3-2 loss to Brighton and Hove Albion on Sunday evening to lose successive games at the Amex Stadium.
Manchester United slumped to a 1-0 defeat at the end of the 2017-18 season and Chris Hughton’s men were comfortable winners at the weekend.
Romelu Lukaku scored what ultimately was a consolation goal before the Red Devils conceded a third goal in the second half to end the tie as a contest.
Manchester United have already lost ground on defending Premier League champions Manchester City following the opening two games of the season.
The Red Devils haven’t won the Premier League since 2013 when Sir Alex Ferguson was still in charge of the Manchester United outfit.
The 20-time English champions’ will take on title rivals Tottenham Hotspur at Old Trafford next Monday night.
Former Manchester United defender Neville believes the Red Devils are facing a difficult week.
“It will be a dark eight days before the Tottenham game because the pressure will come and the media will be all over them like a rash,” Neville told Sky Sports.
“The fans behind the goal spoke with their actions at the end. I’m sure they will be absolutely furious by what they’ve seen.”
Manchester United signed Shakhtar Donetsk midfielder Fred, FC Porto defender Diogo Dalot and Stoke City goalkeeper Lee Grant in the 2018 summer transfer window.
The Red Devils failed to win the FA Cup last term.
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