The Red Devils finished the 2017-18 season without silverware following a 1-0 loss to Chelsea FC at Wembley back in May.
Manchester United have signed Shakhtar Donetsk star Fred, FC Porto defender Diogo Dalot and Stoke goalkeeper Lee Grant in the summer.
However, the Red Devils have seen their title rivals such as Arsenal and Liverpool FC significantly strengthen their squad.
Mourinho won the Europa League and the League Cup in his first season in charge of the Old Trafford outfit.
Former Liverpool FC captain Redknapp wants to see Mourinho improve his mood following his downbeat media conferences throughout pre season.
“I want to see the spark in his eyes again,” Redknapp told the Sky Sports Transfer Talk podcast. “He is a great manager. He has the dream job.”
Manchester United turned to Mourinho after Louis van Gaal led the Red Devils to a fifth-placed finish in the Premier League last term.
The 20-time English champions haven’t won the Premier League title since 2013 when Sir Alex Ferguson won his 13th top flight crown.
The Red Devils failed to win a trophy last season to heap pressure on Mourinho ahead of his third campaign at Old Trafford.
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