The 20-time English champions produced an abysmal performance at the London Stadium to succumb to their third Premier League loss of the current campaign.
Manchester United showed a lack of desire and fight as Manuel Pellegrini’s men eased to a comfortable win and relegated the Red Devils to tenth place in the Premier League table.
Mourinho took charge of Manchester United’s second Champions League fixture at Old Trafford on Tuesday night despite reports continuing to link Zinedine Zidane with his role.
Manchester United, though, were disappointing in a goalless draw with Valencia in the Champions League at Old Trafford despite the best efforts of Marcus Rashford.
Former England midfielder Scholes admitted his surprise that Mourinho was still in charge of the Red Devils for the Champions League clash on Tuesday night.
“I am sat here actually surprised he survived after Saturday, the performance was that bad,” Scholes told BT Sport.
Manchester United are in second spot in their Champions League group after Juventus eased to a 3-0 win over Young Boys in Turin earlier on Tuesday night.
The Red Devils will host Rafael Benitez’s struggling Newcastle United outfit at Old Trafford on Saturday evening in search of their first win in five games.
Scholes, who won 11 Premier League titles and the Champions League twice, slammed Mourinho’s management of the Red Devils squad in the current campaign.
Scholes added: “He’s constantly having a go at players. He’s having a go at those above him because he’s not getting what he wants. I think his mouth is probably out of control and I think he’s embarrassing the club.”
Manchester United have already lost to Brighton and Hove Albion, Tottenham Hotspur and West Ham United in the Premier League to leave them nine points adrift of leaders Manchester City and Liverpool FC.
The Red Devils will be hoping to end a miserable run with a much-needed victory over Newcastle in Saturday’s late kick-off as the Magpies look to end a run of four losses and two draws in their last six outings.
Manchester United lost 1-0 to Newcastle in their last meeting at St James’ Park in February.
Mourinho’s side eased to a 4-1 victory over the Magpies in their most recent clash at Old Trafford.
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