The Red Devils lost 1-0 to Premier League strugglers Newcastle United at St James’ Park last weekend following Matt Ritchie’s second-half winner.
Manchester United are in second place in the Premier League table but 16 points adrift of runaway leaders Manchester City in the title race.
The 20-time English champions are two points ahead of third-placed Liverpool FC in what promises to be a competitive race to secure a top-four spot.
Mourinho led Manchester United to the Europa League and the League Cup titles last season in the Portuguese coach’s first campaign in charge.
However, the Red Devils aren’t closer to Premier League title glory under Mourinho and Manchester United have lost to Chelsea, Manchester City and Tottenham this term.
The former Inter Milan and Real Madrid boss signed a new three-year contract with the 20-time English champions earlier this month despite their inconsistent form in the Premier League.
Former Liverpool FC captain Redknapp is bemused by Manchester United’s decision to hand the outspoken manager a new contract given their current league position.
“When Manchester United extended Jose Mourinho’s contract with a year and a half to run, I was genuinely surprised,” Redknapp told the Daily Mail. “What has he done to earn it?
“Yes, he has won two trophies — the League Cup and Europa League — and restored United to the Champions League, where they are in the last 16.
“But this was the man brought in to go toe-to-toe with Pep Guardiola. Defeat at Newcastle leaves United trailing Manchester City by 16 points.”
Manchester United will take on Huddersfield Town at Old Trafford in the FA Cup fifth round at Old Trafford next weekend.
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