The Red Devils secured second place in the Premier League table on Thursday night thanks to a 0-0 draw with West Ham.
Manchester United produced an uninspiring performance at the London Stadium despite seeing off competition from Liverpool FC for second spot.
Mourinho’s side are a staggering 19 points behind Premier League champions Manchester City in what has been a one-sided title race.
The Red Devils will need to make significant improvements to their squad after Manchester United were left far behind this term.
Manchester United can still finish the season with some silverware if the Red Devils beat Chelsea FC in the FA Cup final at Wembley.
Former Liverpool FC captain Redknapp believes Manchester United have a lot of work to do to overhaul Manchester City.
“I think they’re a long, long way off from competing with Manchester City, if I’m honest. It feels like when Jose went to Real Madrid and had to find a different way to compete with Barcelona and disrupt them,” Redknapp told Sky Sports.
“At the moment, when I look at United, I don’t enjoy watching them. There’s not much fluidity, not much enjoyment. It’s difficult to watch.”
The Red Devils are looking to win their third major trophy under Mourinho after success in the Europa League and League Cup last term.
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