Former Netherlands boss Van Gaal signed a three-year contract when he took over three months after the sacking of David Moyes, who endured a miserable 10 months in charge after replacing the retired Sir Alex Ferguson.
It is unclear whether the 64-year-old Dutchman will see out his final season at Old Trafford, although he said he is “confident” of being in charge.
A number of United supporters have called for the former Ajax, Barcelona and Bayern Munich manager to leave, while some boos could be heard as he addressed the home crowd on a microphone after the final game against Bournemouth.
Van Gaal could lead United to their first major trophy since 2013 – the Premier League title under Ferguson – when they face Crystal Palace in Saturday’s FA Cup final at Wembley.
But he admitted finishing fifth is a step back after guiding the Red Devils to Champions League qualification in his debut season.
“Our aim in the first year – and also the second and the third – is the Champions League,” he said after the 3-1 win over Bournemouth.
“It is the highest level and a club like Manchester United has to play at that level, but there are more clubs that want to play at that level and you have seen that.
“The expectation is very high. The fans are expecting a lot but I think these expectations are much too high.”
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