The Red Devils appointed Mourinho as Louis van Gaal’s successor in May 2016 following a disappointing fifth-placed finish.
Manchester United won the Europa League and the League Cup last term following victories over Dutch giants Ajax and Premier League rivals Southampton.
The 20-time English champions finished in sixth spot but qualified for the Champions League thanks to their Europa League triumph.
Mourinho’s side are in second place in the Premier League this term but 16 points adrift of leaders Manchester City.
The Portuguese coach has been criticised for his team’s lack of adventure in the Champions League and the Premier League this season.
Manchester United have scored 28 goals less than Manchester City to highlight the difference in approach of the two teams.
Former Manchester United defender Parker believes Mourinho hasn’t progressed as a coach unlike his adversary Guardiola.
“Without a doubt the modern game suits Pep Guardiola more than Jose Mourinho. The style of it. The lack of physicality,” said Parker, speaking exclusively to 888Sport.
“Mind games no longer seem to work and trying to stop the play with niggly fouls…the referees can see through all of that now and will penalise.
“The Premier League now gives teams who want to play football every opportunity to do so and that’s because it’s a business now and customers want value for money.
“If people don’t get entertained they will go elsewhere.”
Parker added: “When you look at Pep and Jose you have to say there is a massive gap.
“Pep is evolving and he realises that the game offers him more scope now with what he wants to do because of how the game is going.
:Whereas Mourinho as a coach he’s not really evolved and he’s still doing what he did at Porto and Inter Milan. You have to move on.
“Sir Alex moved on and got different coaches who had different coaches and because of that United still won titles and still dominated.
“You want players to move on and to improve but really it comes down to getting the right teacher, a person who doesn’t only believe in himself but in the abilities of the player and what they can do.”
Manchester United signed Chile international Alexis Sanchez from Arsenal in a swap deal from the January transfer window.
The South American has only scored two goals in 12 games in all competitions since his controversial switch to Manchester United.
Read the full 888sport interview with Paul Parker, including his prediction for the Manchester Derby this weekend
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