The Red Devils were held to a goalless draw with West Ham United at the London Stadium on Thursday night.
Manchester United secured second place in the Premier League table thanks to their stalemate in east London.
However, the Red Devils have continued their inconsistent form in front of goal with another disappointing attacking display.
While Manchester United are in second spot, Liverpool FC have scored 16 goals more than their rivals.
Tottenham Hotspur have also found the net more times than Mourinho’s side to fuel criticism of Mourinho’s style of play.
Former Liverpool FC star Redknapp admitted that he doesn’t find it enjoyable to watch Manchester United.
“United fans have been blessed watching some great sides but it’s hard to watch this United side,” Redknapp told Sky Sports.
“There’s not a lot of joy in their play. I still think (Jose’s) searching for something when you look at the teams and systems.”
The Red Devils will take on Chelsea FC in the FA Cup final at Wembley later this month.
Manchester United were 2-1 winners against Tottenham Hotspur in the FA Cup semi-final at Wembley.
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