The Red Devils slumped to their third Premier League loss of the season to fall further behind their title rivals after seven games.
Manchester United have lost to Brighton, Tottenham Hotspur and West Ham to fall nine points behind leaders Manchester City and Liverpool FC in the title race.
Jose Mourinho was thought to have been upset with Manchester United chief executive Ed Woodward after the Red Devils missed out on some key signings.
Paul Pogba was critical of their tactics in a 1-1 draw with promoted side Wolverhampton Wanderers at Old Trafford last month.
The Manchester United manager stripped the club record signing of the vice captaincy following his comments about the stalemate with Wolves.
Former England international Scholes reckons his former club are in turmoil to heap pressure on Mourinho.
“At this minute, I think this club seems to be in a bit of a mess,” Scholes told BT Sport.
“Whether it’s from above Mourinho… we know he didn’t get the players he wanted in the summer.
“We know he’s been given a lot of money to spend on players. It just seems like a war throughout the club, Ed Woodward to Mourinho and Mourinho to his players. The players just look unstable.”
Manchester United finished in second place in the Premier League table last term to secure their best finish since the Sir Alex Ferguson era.
The Red Devils signed Shakhtar Donetsk midfielder Fred, FC Porto defender Diogo Dalot and Stoke goalkeeper Lee Grant in the summer transfer window.
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