The Reds have been in much more consistent form in the Premier League this season and they secured a second-placed finish behind Manchester City, in what is their best finish in the top flight since Sir Alex Ferguson’s retirement in 2013.
Both Chelsea FC and Manchester United now face the FA Cup final as their final chance of winning a piece of silverware this season.
And former Manchester United defender Neville has talked up the importance of the Red Devils beating Chelsea FC in the final at Wembley on Saturday to make this campaign a successful one.
Speaking to Sky Sports, Neville said: “The FA Cup final next Saturday against Chelsea will ultimately decide whether this season is seen as progression or not for Manchester United.
“In the league, which is where everybody wants to be measured, you have to say that second is progression from where Manchester United have been, but it’s not a successful season for Manchester United when you don’t win the league.
“That’s the measure of the club and has been for 60, 70, 80 years, it has to be the league title you are measured by.”
Manchester United won both the Europa League and League Cup in Mourinho’s first campaign in charge at Old Trafford last season.
The Red Devils are likely to try and bring in a number of new players this summer as Mourinho looks to build a squad capable of challenging Manchester City’s dominance in the Premier League next season.
Manchester United have not won the title since Ferguson’s final campaign in charge in 2013.
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