The Red Devils are in second place in the Premier League table and two points ahead of Liverpool FC in the race to finish in the top four.
Manchester United suffered a 2-1 aggregate loss to La Liga outfit Sevilla in the Champions League round of 16.
The 20-time English champions are in the FA Cup semi-finals after a 2-0 win over Brighton and Hove Albion last weekend.
Manchester United are a staggering 16 points adrift of runaway Premier League leaders Manchester City.
Jose Mourinho has signed eight players since his appointment as Louis van Gaal’s successor in May 2016.
Former Tottenham star Mason believes Manchester United are still a long way short of title glory.
“I don’t think so,” Mason told Sky Sports. “They need a massive overhaul of players to win the title next season.”
Manchester United finished in sixth place in the Premier League table last term.
The Red Devils have won the Europa League and the League Cup in Mourinho’s first season in charge.
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