The Red Devils ended up in second spot in the Premier League table last term to secure their best finish since Sir Alex Ferguson was in charge.
However, Manchester United failed to substantially improve their squad in the summer to leave the Red Devils off the pace in the title race.
Indeed, Liverpool FC and Manchester City have already built a substantial lead over Manchester United in the opening months of the season.
Mourinho’s side suffered an 8-7 penalty shootout loss to Championship side Derby County in the League Cup third round at Old Trafford – and they then lost 3-1 to West Ham in the Premier League on Saturday to leave them 10th in the table.
Former Arsenal star Merson believes Manchester United are competing for a top four finish in the current campaign.
“They are looking for a top four place,” Merson told Sky Sports. “That’s what they’re fighting for.”
Manchester United signed Shakhtar Donetsk midfielder Fred, FC Porto defender Diogo Dalot and Stoke City goalkeeper Lee Grant in the summer.
The Red Devils have won the Europa League and the League Cup since Mourinho took over the reins from Van Gaal little over two seasons ago.
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