The Red Devils finished in second place in the Premier League table last term but the 20-time English champions finished a long way behind champions Manchester City.
Manchester United ended up 19 points adrift of their derby rivals, while Mourinho was criticised for his side’s unadventurous style of play in the Premier League.
Pogba was often ommitted from Mourinho’s starting line up due to his ineffective performances in the middle of the park, while January signing Sanchez failed to hit the ground running following his switch from Arsenal.
Manchester United have signed Shakhtar Donetsk star Fred, FC Porto teenager Diogo Dalot and Stoke goalkeeper Lee Grant in the summer transfer window, but the Red Devils failed to address key areas at centre-half and the right wing.
Former Manchester United striker Owen ruled out the Red Devils launching a sustained challenge in the Premier League this season.
“The Red Devils finished runners up last season, but I don’t think they will emerge as realistic title contenders or neighbours City’s biggest challengers for the title this season,” Owen told BetVictor. “This is a potentially defining season for United’s big players Paul Pogba and Alexis Sanchez and, indeed, for manager Jose Mourinho.”
The Red Devils haven’t won the Premier League title since 2013 when Sir Alex Ferguson got his hands on his 13th an final top-flight crown.
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