The Dutchman says he could not have anticipated his side's dreadful start to the 3-0 loss at Arsenal.
Louis van Gaal insists Manchester United's under-par first-half performance against Arsenal on Sunday came as a big surprise to him.
United was beaten 3-0 by Arsene Wenger's side, with all three goals coming in the first 20 minutes through Alexis Sanchez (2) and Mesut Ozil.
Following the defeat, which sees United drop to third place in the Premier League table, the Dutchman railed against the idea that the performance had been on the cards.
"We didn't expect it.