The Red Devils were 4-2 winners against Watford at Vicarage Road on Tuesday night thanks to goals from Ashley Young, Anthony Martial and Jesse Lingard.
Manchester United moved eight points clear of fourth-placed Arsenal ahead of the north London side’s home clash against Huddersfield Town on Wednesday night.
The 20-time English champions have only managed to collect four points from their three Premier League fixtures against their direct title rivals in the 2017-18 season so far.
Manchester United drew 0-0 with Jurgen Klopp’s Liverpool side at Anfield before the Red Devils were unconvincing 1-0 winners against Tottenham Hotspur at Old Trafford.
Mourinho’s men lost 1-0 to defending Premier League champions Chelsea at Stamford Bridge at the weekend following Alvaro Morata’s 55th-minute winner in west London.
Former Manchester United midfielder Scholes warned Mourinho’s side that the Red Devils can’t afford to underestimate Arsenal ahead of their clash at The Emirates this weekend.
“Saturday against Arsenal is a big game and they have to turn up,” Scholes told BT Sport.
“It’s very difficult to criticise when you’re winning games, especially when you’re scoring four goals. But they’ve really got to turn up in these big games and win some of them.”
Manchester United finished in sixth place in the Premier League table last season but won the League Cup and the Europa League thanks to victories over Southampton and Ajax.
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