The Red Devils slumped to a surprise 1-0 loss to West Bromwich Albion in the Premier League at Old Trafford on Sunday evening.
Jay Rodriguez netted a 73rd-minute winner to secure three points for the 20th-placed Premier League team despite their well-documented struggles this term.
Manchester United have only managed to score 35 times in their 17 games at Old Trafford in the Premier League this term.
The Red Devils have netted less goals than Manchester City, Liverpool FC and Arsenal at home, although only the Premier League champions have a better record at home than Manchester United.
Mourinho was quick to criticise his players following their frustrating 1-0 loss to West Brom on Sunday evening as Manchester United offered Liverpool FC some hope in the race to finish in second place.
Former Arsenal star Merson hasn’t been impressed with Manchester United’s uninspiring style of play under Mourinho this term.
Merson told Sky Sports: “It was too slow. It’s not been good. They’ve been terrible to watch, and they’ve got enough attacking flair. It’s not like you’re sat there thinking: “Who can they bring on here?”
Manchester United will take on Tottenham Hotspur in the FA Cup semi-finals at Wembley later this month.
The Red Devils won the Europa League and the League Cup in their first season under Mourinho.
Manchester United signed Alexis Sanchez in a swap deal from Arsenal in the January transfer window.
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