The Red Devils are currently six points off the pace in the race for the Premier League title this season after having lost their last two games in the top flight.
Jose Mourinho has found himself under intense pressure already following his side’s lacklustre displays against Brighton and Hove Albion and Tottenham Hotspur.
Manchester United will be aiming to get back to winning ways in the top flight when the Red Devils take on Burnley away from home on Sunday afternoon.
However, former Manchester United goalkeeper Van Der Sar has admitted that he is concerned about his ex-club’s current situation.
Speaking in an interview quoted by the Daily Express, Van Der Sar said: “Last year, there was a very big gap [to Manchester City] and this year they’ve started badly, losing two of their first three games.
“It will be an uphill battle. You have so many strong teams in the Premier League.
“It is going to be difficult this year.”
Manchester United ended up in second place in the Premier League and without a trophy last season under Mourinho.
The Red Devils had won the Europa League and League Cup in Mourinho’s first campaign in charge but they have struggled to produce consistent form recently.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news